Data Wrangling with dplyr

Tuesday, October 8

Today we will…

Comments from Week 2

  • Read through your .html to make sure it looks correct.
    • Is any of your code producing errors / warnings / messages?
    • Are images appearing properly?
    • Are hyperlinks working properly?

. . .

  • Do not install packages in Quarto code chunks!
    • Remember: we only install packages once.

. . .

  • Make sure you cite external sources.
    • E.g., many people used sapply() to get the variable data types – this is fine, but where did you find this solution? It’s not in the textbook or the coursework, so that function requires a citation!

Citing Your Sources

When you write code, you will need to reference function / package documentation and external resources.

  • This is part of being a programmer!

. . .

When you rely on external resources for an assignment in this course, you must cite your sources.

  • If you use any resources outside of the course text, the course slides, and the posted cheatsheets, you must include a citation!
  • If you do not cite your sources that constitutes plagiarism.
  • Any instances of plagiarism in a lab or challenge assignment removes your ability to include code from that assignment in your portfolio.

Data Wrangling with dplyr

A cartoon illustration of a cowboy riding a dataset, symbolized by a saddle on top of a spreadsheet. The cowboy is wearing a hat and bandana, with the reins in one hand and a lasso in the other, as if wrangling data. The dataset underneath has rows and columns, representing organized data. The image humorously conveys the idea of managing and working with data.

Artwork by Allison Horst

dplyr

dplyr is part of the tidyverse that provides us with the Grammar of Data Manipulation.

  • This package gives us the tools to wrangle, manipulate, and tidy our data with ease.
  • Check out the dplyr cheatsheet.

A hexagonal-shaped logo featuring three colorful pliers in red, blue, and orange shades, aligned diagonally. The word 'dplyr' is written at the top in gray, and the bottom right corner shows the URL 'dplyr.tidyverse.org'. The background consists of diagonal black and gray stripes with colorful hexagons scattered around, symbolizing data manipulation and transformation tools, representing the dplyr package from the tidyverse ecosystem in R.

dplyr verbs

  • filter() – select rows based on their values
  • select() – select columns
  • mutate() – add new columns or change existing columns
  • summarize() – perform summary operations on columns
  • group_by() – facilitate group-wise operations
  • arrange() – sort rows based on their values

. . .

Use the pipe operator (|> or %>%) to chain together data wrangling operations.

The Pipe Operator

No matter how complex and polished the individual operations are, it is often the quality of the glue that most directly determines the power of the system.

— Hal Abelson

The Pipe Operator

  • With dplyr, your code should read like a sentence.

  • The data is the primary object in your sentence, so it should come first in your code.

knitr::include_graphics("images/diagram_sentence.jpg")

  • The pipe operator is an important part of that readability.

The Pipe Operator

  • The pipe specifies a sequence of operations.
    • The output from one operation is passed into the first argument (the dataset) of the next operation.

. . .

  • The “original” pipe: %>%

    • Loaded with tidyverse package (part of magrittr).

  • The “native” pipe: |>

    • Created in R version 4.1.0.
    • Tools > Global Options... > Code > check Use native pipe operator box.

The Pipe Operator

dr_theobold |>
  play_a_sport()

. . .


dr_theobold |>
  put_on("cleats") |>
  play_a_sport(type = "track")

Data Comes First!

  • filter(.data = cereal, ...)
  • select(.data = cereal, ...)
  • mutate(.data = cereal, ...)

. . .

You can choose whether to:

declare your data using the .data argument

summary(.data = cereal)

or

pipe your data into the first argument of the function

cereal |> 
  summary()

I ❤️ |>


The pipe operator is your friend!

You can pipe data or summaries directly into your ggplot2 code for plotting!


cereals |>
  mutate(type = as.factor(type)) |> 
  rename(temp = type) |>  
  filter(temp == "C") |>
  ggplot(mapping = aes(x = calories)) +
    geom_histogram(binwidth = 17)

Example Data set – Cereal

library(liver)

Attaching package: 'liver'
The following object is masked from 'package:base':

    transform
data(cereal)

. . .

glimpse(cereal)
Rows: 77
Columns: 16
$ name     <fct> 100% Bran, 100% Natural Bran, All-Bran, All-Bran with Extra F…
$ manuf    <fct> N, Q, K, K, R, G, K, G, R, P, Q, G, G, G, G, R, K, K, G, K, N…
$ type     <fct> cold, cold, cold, cold, cold, cold, cold, cold, cold, cold, c…
$ calories <int> 70, 120, 70, 50, 110, 110, 110, 130, 90, 90, 120, 110, 120, 1…
$ protein  <int> 4, 3, 4, 4, 2, 2, 2, 3, 2, 3, 1, 6, 1, 3, 1, 2, 2, 1, 1, 3, 3…
$ fat      <int> 1, 5, 1, 0, 2, 2, 0, 2, 1, 0, 2, 2, 3, 2, 1, 0, 0, 0, 1, 3, 0…
$ sodium   <int> 130, 15, 260, 140, 200, 180, 125, 210, 200, 210, 220, 290, 21…
$ fiber    <dbl> 10.0, 2.0, 9.0, 14.0, 1.0, 1.5, 1.0, 2.0, 4.0, 5.0, 0.0, 2.0,…
$ carbo    <dbl> 5.0, 8.0, 7.0, 8.0, 14.0, 10.5, 11.0, 18.0, 15.0, 13.0, 12.0,…
$ sugars   <int> 6, 8, 5, 0, 8, 10, 14, 8, 6, 5, 12, 1, 9, 7, 13, 3, 2, 12, 13…
$ potass   <int> 280, 135, 320, 330, -1, 70, 30, 100, 125, 190, 35, 105, 45, 1…
$ vitamins <int> 25, 0, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25…
$ shelf    <int> 3, 3, 3, 3, 3, 1, 2, 3, 1, 3, 2, 1, 2, 3, 2, 1, 1, 2, 2, 3, 2…
$ weight   <dbl> 1.00, 1.00, 1.00, 1.00, 1.00, 1.00, 1.00, 1.33, 1.00, 1.00, 1…
$ cups     <dbl> 0.33, 1.00, 0.33, 0.50, 0.75, 0.75, 1.00, 0.75, 0.67, 0.67, 0…
$ rating   <dbl> 68.40297, 33.98368, 59.42551, 93.70491, 34.38484, 29.50954, 3…
summary(cereal)
                        name    manuf    type       calories    
 100% Bran                : 1   A: 1   cold:74   Min.   : 50.0  
 100% Natural Bran        : 1   G:22   hot : 3   1st Qu.:100.0  
 All-Bran                 : 1   K:23             Median :110.0  
 All-Bran with Extra Fiber: 1   N: 6             Mean   :106.9  
 Almond Delight           : 1   P: 9             3rd Qu.:110.0  
 Apple Cinnamon Cheerios  : 1   Q: 8             Max.   :160.0  
 (Other)                  :71   R: 8                            
    protein           fat            sodium          fiber       
 Min.   :1.000   Min.   :0.000   Min.   :  0.0   Min.   : 0.000  
 1st Qu.:2.000   1st Qu.:0.000   1st Qu.:130.0   1st Qu.: 1.000  
 Median :3.000   Median :1.000   Median :180.0   Median : 2.000  
 Mean   :2.545   Mean   :1.013   Mean   :159.7   Mean   : 2.152  
 3rd Qu.:3.000   3rd Qu.:2.000   3rd Qu.:210.0   3rd Qu.: 3.000  
 Max.   :6.000   Max.   :5.000   Max.   :320.0   Max.   :14.000  
                                                                 
     carbo          sugars           potass          vitamins     
 Min.   :-1.0   Min.   :-1.000   Min.   : -1.00   Min.   :  0.00  
 1st Qu.:12.0   1st Qu.: 3.000   1st Qu.: 40.00   1st Qu.: 25.00  
 Median :14.0   Median : 7.000   Median : 90.00   Median : 25.00  
 Mean   :14.6   Mean   : 6.922   Mean   : 96.08   Mean   : 28.25  
 3rd Qu.:17.0   3rd Qu.:11.000   3rd Qu.:120.00   3rd Qu.: 25.00  
 Max.   :23.0   Max.   :15.000   Max.   :330.00   Max.   :100.00  
                                                                  
     shelf           weight          cups           rating     
 Min.   :1.000   Min.   :0.50   Min.   :0.250   Min.   :18.04  
 1st Qu.:1.000   1st Qu.:1.00   1st Qu.:0.670   1st Qu.:33.17  
 Median :2.000   Median :1.00   Median :0.750   Median :40.40  
 Mean   :2.208   Mean   :1.03   Mean   :0.821   Mean   :42.67  
 3rd Qu.:3.000   3rd Qu.:1.00   3rd Qu.:1.000   3rd Qu.:50.83  
 Max.   :3.000   Max.   :1.50   Max.   :1.500   Max.   :93.70

filter()

knitr::include_graphics("https://github.com/allisonhorst/stats-illustrations/raw/main/rstats-artwork/dplyr_filter.jpg")

A cartoon illustration of two characters holding a large, red sieve, filtering out hexagonal shapes from a mix of data. The characters appear focused as they perform this task, representing the concept of filtering data in the 'dplyr' package of R. The hexagons that pass through the sieve are the relevant, filtered data, while others are left behind. The image creatively portrays the function of the 'filter()' tool used in data manipulation.

Artwork by Allison Horst

filter()

We filter to the rows (observations) we would like to keep in the data.

. . .

cereal |> 
  filter(sugars < 5)


name manuf type calories protein fat sodium fiber carbo sugars potass vitamins shelf weight cups rating
All-Bran with Extra Fiber K cold 50 4 0 140 14.0 8 0 330 25 3 1.00 0.50 93.70491
Cheerios G cold 110 6 2 290 2.0 17 1 105 25 1 1.00 1.25 50.76500
Corn Chex R cold 110 2 0 280 0.0 22 3 25 25 1 1.00 1.00 41.44502
Corn Flakes K cold 100 2 0 290 1.0 21 2 35 25 1 1.00 1.00 45.86332
Cream of Wheat (Quick) N hot 100 3 0 80 1.0 21 0 -1 0 2 1.00 1.00 64.53382
Crispix K cold 110 2 0 220 1.0 21 3 30 25 3 1.00 1.00 46.89564
Grape-Nuts P cold 110 3 0 170 3.0 17 3 90 25 3 1.00 0.25 53.37101
Great Grains Pecan P cold 120 3 3 75 3.0 13 4 100 25 3 1.00 0.33 45.81172
Kix G cold 110 2 1 260 0.0 21 3 40 25 2 1.00 1.50 39.24111
Maypo A hot 100 4 1 0 0.0 16 3 95 25 2 1.00 1.00 54.85092
Nutri-grain Wheat K cold 90 3 0 170 3.0 18 2 90 25 3 1.00 1.00 59.64284
Product 19 K cold 100 3 0 320 1.0 20 3 45 100 3 1.00 1.00 41.50354
Puffed Rice Q cold 50 1 0 0 0.0 13 0 15 0 3 0.50 1.00 60.75611
Puffed Wheat Q cold 50 2 0 0 1.0 10 0 50 0 3 0.50 1.00 63.00565
Quaker Oatmeal Q hot 100 5 2 0 2.7 -1 -1 110 0 1 1.00 0.67 50.82839
Rice Chex R cold 110 1 0 240 0.0 23 2 30 25 1 1.00 1.13 41.99893
Rice Krispies K cold 110 2 0 290 0.0 22 3 35 25 1 1.00 1.00 40.56016
Shredded Wheat N cold 80 2 0 0 3.0 16 0 95 0 1 0.83 1.00 68.23588
Shredded Wheat 'n'Bran N cold 90 3 0 0 4.0 19 0 140 0 1 1.00 0.67 74.47295
Shredded Wheat spoon size N cold 90 3 0 0 3.0 20 0 120 0 1 1.00 0.67 72.80179
Special K K cold 110 6 0 230 1.0 16 3 55 25 1 1.00 1.00 53.13132
Total Corn Flakes G cold 110 2 1 200 0.0 21 3 35 100 3 1.00 1.00 38.83975
Total Whole Grain G cold 100 3 1 200 3.0 16 3 110 100 3 1.00 1.00 46.65884
Triples G cold 110 2 1 250 0.0 21 3 60 25 3 1.00 0.75 39.10617
Wheat Chex R cold 100 3 1 230 3.0 17 3 115 25 1 1.00 0.67 49.78744
Wheaties G cold 100 3 1 200 3.0 17 3 110 25 1 1.00 1.00 51.59219

filter()

We can add multiple filters to our data, to get a more specific subset.

cereal |> 
  filter(sugars < 5,
         type == "hot")


name manuf type calories protein fat sodium fiber carbo sugars potass vitamins shelf weight cups rating
Cream of Wheat (Quick) N hot 100 3 0 80 1.0 21 0 -1 0 2 1 1.00 64.53382
Maypo A hot 100 4 1 0 0.0 16 3 95 25 2 1 1.00 54.85092
Quaker Oatmeal Q hot 100 5 2 0 2.7 -1 -1 110 0 1 1 0.67 50.82839

Why not use &?

The , separating these two conditions is equivalent to using an &.

. . .

Why not just use a &?

Well, with a lot of &s your code can get hard to read…

. . .

filter(sugars < 5 & type == "cold" & calories > 100)

filter(): Handy Helpers!

  • > : greater than
  • < : less than
  • == : equal to
  • ! : not
  • %in% : checks if an element belongs to a vector
  • is.na() : binary evaluation of missing values
  • | : or

filter(): |

What if I wanted either non-sugary cereals or hot cereals…

. . .

cereal |> 
  filter(sugars < 5 |
           type == "hot")
name manuf type calories protein fat sodium fiber carbo sugars potass vitamins shelf weight cups rating
All-Bran with Extra Fiber K cold 50 4 0 140 14.0 8 0 330 25 3 1.00 0.50 93.70491
Cheerios G cold 110 6 2 290 2.0 17 1 105 25 1 1.00 1.25 50.76500
Corn Chex R cold 110 2 0 280 0.0 22 3 25 25 1 1.00 1.00 41.44502
Corn Flakes K cold 100 2 0 290 1.0 21 2 35 25 1 1.00 1.00 45.86332
Cream of Wheat (Quick) N hot 100 3 0 80 1.0 21 0 -1 0 2 1.00 1.00 64.53382
Crispix K cold 110 2 0 220 1.0 21 3 30 25 3 1.00 1.00 46.89564
Grape-Nuts P cold 110 3 0 170 3.0 17 3 90 25 3 1.00 0.25 53.37101
Great Grains Pecan P cold 120 3 3 75 3.0 13 4 100 25 3 1.00 0.33 45.81172
Kix G cold 110 2 1 260 0.0 21 3 40 25 2 1.00 1.50 39.24111
Maypo A hot 100 4 1 0 0.0 16 3 95 25 2 1.00 1.00 54.85092
Nutri-grain Wheat K cold 90 3 0 170 3.0 18 2 90 25 3 1.00 1.00 59.64284
Product 19 K cold 100 3 0 320 1.0 20 3 45 100 3 1.00 1.00 41.50354
Puffed Rice Q cold 50 1 0 0 0.0 13 0 15 0 3 0.50 1.00 60.75611
Puffed Wheat Q cold 50 2 0 0 1.0 10 0 50 0 3 0.50 1.00 63.00565
Quaker Oatmeal Q hot 100 5 2 0 2.7 -1 -1 110 0 1 1.00 0.67 50.82839
Rice Chex R cold 110 1 0 240 0.0 23 2 30 25 1 1.00 1.13 41.99893
Rice Krispies K cold 110 2 0 290 0.0 22 3 35 25 1 1.00 1.00 40.56016
Shredded Wheat N cold 80 2 0 0 3.0 16 0 95 0 1 0.83 1.00 68.23588
Shredded Wheat 'n'Bran N cold 90 3 0 0 4.0 19 0 140 0 1 1.00 0.67 74.47295
Shredded Wheat spoon size N cold 90 3 0 0 3.0 20 0 120 0 1 1.00 0.67 72.80179
Special K K cold 110 6 0 230 1.0 16 3 55 25 1 1.00 1.00 53.13132
Total Corn Flakes G cold 110 2 1 200 0.0 21 3 35 100 3 1.00 1.00 38.83975
Total Whole Grain G cold 100 3 1 200 3.0 16 3 110 100 3 1.00 1.00 46.65884
Triples G cold 110 2 1 250 0.0 21 3 60 25 3 1.00 0.75 39.10617
Wheat Chex R cold 100 3 1 230 3.0 17 3 115 25 1 1.00 0.67 49.78744
Wheaties G cold 100 3 1 200 3.0 17 3 110 25 1 1.00 1.00 51.59219

filter(): %in%

Are you interested in observations with values in a list of levels?

. . .

cereal |> 
  filter(name %in% c("Cheerios", 
                     "Cinnamon Toast Crunch", 
                     "Raisin Bran", 
                     "Cracklin' Oat Bran")
         )
name manuf type calories protein fat sodium fiber carbo sugars potass vitamins shelf weight cups rating
Cheerios G cold 110 6 2 290 2 17 1 105 25 1 1.00 1.25 50.76500
Cinnamon Toast Crunch G cold 120 1 3 210 0 13 9 45 25 2 1.00 0.75 19.82357
Cracklin' Oat Bran K cold 110 3 3 140 4 10 7 160 25 3 1.00 0.50 40.44877
Raisin Bran K cold 120 3 1 210 5 14 12 240 25 2 1.33 0.75 39.25920

How do we “filter” in base R?

You can use the subset() function!

cereal |> 
  subset(name %in% c("Cheerios", 
                     "Cinnamon Toast Crunch", 
                     "Raisin Bran", 
                     "Cracklin' Oat Bran")
         )
name manuf type calories protein fat sodium fiber carbo sugars potass vitamins shelf weight cups rating
12 Cheerios G cold 110 6 2 290 2 17 1 105 25 1 1.00 1.25 50.76500
13 Cinnamon Toast Crunch G cold 120 1 3 210 0 13 9 45 25 2 1.00 0.75 19.82357
20 Cracklin' Oat Bran K cold 110 3 3 140 4 10 7 160 25 3 1.00 0.50 40.44877
59 Raisin Bran K cold 120 3 1 210 5 14 12 240 25 2 1.33 0.75 39.25920

Another example of the subset() function…

cereal |> 
  subset(sugars < 5 & type == "hot")
name manuf type calories protein fat sodium fiber carbo sugars potass vitamins shelf weight cups rating
21 Cream of Wheat (Quick) N hot 100 3 0 80 1.0 21 0 -1 0 2 1 1.00 64.53382
44 Maypo A hot 100 4 1 0 0.0 16 3 95 25 2 1 1.00 54.85092
58 Quaker Oatmeal Q hot 100 5 2 0 2.7 -1 -1 110 0 1 1 0.67 50.82839

arrange()

arrange()

We arrange the rows of the data in order of a particular variable.

. . .


cereal |> 
  arrange(sodium)


name manuf type calories protein fat sodium fiber carbo sugars potass vitamins shelf weight cups rating
Frosted Mini-Wheats K cold 100 3 0 0 3.0 14.0 7 100 25 2 1.00 0.80 58.34514
Maypo A hot 100 4 1 0 0.0 16.0 3 95 25 2 1.00 1.00 54.85092
Puffed Rice Q cold 50 1 0 0 0.0 13.0 0 15 0 3 0.50 1.00 60.75611
Puffed Wheat Q cold 50 2 0 0 1.0 10.0 0 50 0 3 0.50 1.00 63.00565
Quaker Oatmeal Q hot 100 5 2 0 2.7 -1.0 -1 110 0 1 1.00 0.67 50.82839
Raisin Squares K cold 90 2 0 0 2.0 15.0 6 110 25 3 1.00 0.50 55.33314
Shredded Wheat N cold 80 2 0 0 3.0 16.0 0 95 0 1 0.83 1.00 68.23588
Shredded Wheat 'n'Bran N cold 90 3 0 0 4.0 19.0 0 140 0 1 1.00 0.67 74.47295
Shredded Wheat spoon size N cold 90 3 0 0 3.0 20.0 0 120 0 1 1.00 0.67 72.80179
100% Natural Bran Q cold 120 3 5 15 2.0 8.0 8 135 0 3 1.00 1.00 33.98368
Strawberry Fruit Wheats N cold 90 2 0 15 3.0 15.0 5 90 25 2 1.00 1.00 59.36399
Golden Crisp P cold 100 2 0 45 0.0 11.0 15 40 25 1 1.00 0.88 35.25244
Smacks K cold 110 2 1 70 1.0 9.0 15 40 25 2 1.00 0.75 31.23005
Great Grains Pecan P cold 120 3 3 75 3.0 13.0 4 100 25 3 1.00 0.33 45.81172
Cream of Wheat (Quick) N hot 100 3 0 80 1.0 21.0 0 -1 0 2 1.00 1.00 64.53382
Corn Pops K cold 110 1 0 90 1.0 13.0 12 20 25 2 1.00 1.00 35.78279
Muesli Raisins; Dates; & Almonds R cold 150 4 3 95 3.0 16.0 11 170 25 3 1.00 1.00 37.13686
Apple Jacks K cold 110 2 0 125 1.0 11.0 14 30 25 2 1.00 1.00 33.17409
Froot Loops K cold 110 2 1 125 1.0 11.0 13 30 25 2 1.00 1.00 32.20758
100% Bran N cold 70 4 1 130 10.0 5.0 6 280 25 3 1.00 0.33 68.40297
Fruity Pebbles P cold 110 1 1 135 0.0 13.0 12 25 25 2 1.00 0.75 28.02576
Quaker Oat Squares Q cold 100 4 1 135 2.0 14.0 6 110 25 3 1.00 0.50 49.51187
All-Bran with Extra Fiber K cold 50 4 0 140 14.0 8.0 0 330 25 3 1.00 0.50 93.70491
Clusters G cold 110 3 2 140 2.0 13.0 7 105 25 3 1.00 0.50 40.40021
Cracklin' Oat Bran K cold 110 3 3 140 4.0 10.0 7 160 25 3 1.00 0.50 40.44877
Crispy Wheat & Raisins G cold 100 2 1 140 2.0 11.0 10 120 25 3 1.00 0.75 36.17620
Grape Nuts Flakes P cold 100 3 1 140 3.0 15.0 5 85 25 3 1.00 0.88 52.07690
Raisin Nut Bran G cold 100 3 2 140 2.5 10.5 8 140 25 3 1.00 0.50 39.70340
Trix G cold 110 1 1 140 0.0 13.0 12 25 25 2 1.00 1.00 27.75330
Life Q cold 100 4 2 150 2.0 12.0 6 95 25 2 1.00 0.67 45.32807
Muesli Raisins; Peaches; & Pecans R cold 150 4 3 150 3.0 16.0 11 170 25 3 1.00 1.00 34.13976
Mueslix Crispy Blend K cold 160 3 2 150 3.0 17.0 13 160 25 3 1.50 0.67 30.31335
Fruit & Fibre Dates; Walnuts; and Oats P cold 120 3 2 160 5.0 12.0 10 200 25 3 1.25 0.67 40.91705
Grape-Nuts P cold 110 3 0 170 3.0 17.0 3 90 25 3 1.00 0.25 53.37101
Just Right Crunchy Nuggets K cold 110 2 1 170 1.0 17.0 6 60 100 3 1.00 1.00 36.52368
Just Right Fruit & Nut K cold 140 3 1 170 2.0 20.0 9 95 100 3 1.30 0.75 36.47151
Nutri-grain Wheat K cold 90 3 0 170 3.0 18.0 2 90 25 3 1.00 1.00 59.64284
Oatmeal Raisin Crisp G cold 130 3 2 170 1.5 13.5 10 120 25 3 1.25 0.50 30.45084
Apple Cinnamon Cheerios G cold 110 2 2 180 1.5 10.5 10 70 25 1 1.00 0.75 29.50954
Cocoa Puffs G cold 110 1 1 180 0.0 12.0 13 55 25 2 1.00 1.00 22.73645
Count Chocula G cold 110 1 1 180 0.0 12.0 13 65 25 2 1.00 1.00 22.39651
Honey-comb P cold 110 1 0 180 0.0 14.0 11 35 25 1 1.00 1.33 28.74241
Lucky Charms G cold 110 2 1 180 0.0 12.0 12 55 25 2 1.00 1.00 26.73451
Double Chex R cold 100 2 0 190 1.0 18.0 5 80 25 3 1.00 0.75 44.33086
Nut&Honey Crunch K cold 120 2 1 190 0.0 15.0 9 40 25 2 1.00 0.67 29.92429
Total Raisin Bran G cold 140 3 1 190 4.0 15.0 14 230 100 3 1.50 1.00 28.59278
Almond Delight R cold 110 2 2 200 1.0 14.0 8 -1 25 3 1.00 0.75 34.38484
Bran Chex R cold 90 2 1 200 4.0 15.0 6 125 25 1 1.00 0.67 49.12025
Frosted Flakes K cold 110 1 0 200 1.0 14.0 11 25 25 1 1.00 0.75 31.43597
Post Nat. Raisin Bran P cold 120 3 1 200 6.0 11.0 14 260 25 3 1.33 0.67 37.84059
Total Corn Flakes G cold 110 2 1 200 0.0 21.0 3 35 100 3 1.00 1.00 38.83975
Total Whole Grain G cold 100 3 1 200 3.0 16.0 3 110 100 3 1.00 1.00 46.65884
Wheaties G cold 100 3 1 200 3.0 17.0 3 110 25 1 1.00 1.00 51.59219
Wheaties Honey Gold G cold 110 2 1 200 1.0 16.0 8 60 25 1 1.00 0.75 36.18756
Basic 4 G cold 130 3 2 210 2.0 18.0 8 100 25 3 1.33 0.75 37.03856
Bran Flakes P cold 90 3 0 210 5.0 13.0 5 190 25 3 1.00 0.67 53.31381
Cinnamon Toast Crunch G cold 120 1 3 210 0.0 13.0 9 45 25 2 1.00 0.75 19.82357
Raisin Bran K cold 120 3 1 210 5.0 14.0 12 240 25 2 1.33 0.75 39.25920
Cap'n'Crunch Q cold 120 1 2 220 0.0 12.0 12 35 25 2 1.00 0.75 18.04285
Crispix K cold 110 2 0 220 1.0 21.0 3 30 25 3 1.00 1.00 46.89564
Honey Graham Ohs Q cold 120 1 2 220 1.0 12.0 11 45 25 2 1.00 1.00 21.87129
Multi-Grain Cheerios G cold 100 2 1 220 2.0 15.0 6 90 25 1 1.00 1.00 40.10596
Nutri-Grain Almond-Raisin K cold 140 3 2 220 3.0 21.0 7 130 25 3 1.33 0.67 40.69232
Special K K cold 110 6 0 230 1.0 16.0 3 55 25 1 1.00 1.00 53.13132
Wheat Chex R cold 100 3 1 230 3.0 17.0 3 115 25 1 1.00 0.67 49.78744
Fruitful Bran K cold 120 3 0 240 5.0 14.0 12 190 25 3 1.33 0.67 41.01549
Rice Chex R cold 110 1 0 240 0.0 23.0 2 30 25 1 1.00 1.13 41.99893
Honey Nut Cheerios G cold 110 3 1 250 1.5 11.5 10 90 25 1 1.00 0.75 31.07222
Triples G cold 110 2 1 250 0.0 21.0 3 60 25 3 1.00 0.75 39.10617
All-Bran K cold 70 4 1 260 9.0 7.0 5 320 25 3 1.00 0.33 59.42551
Kix G cold 110 2 1 260 0.0 21.0 3 40 25 2 1.00 1.50 39.24111
Corn Chex R cold 110 2 0 280 0.0 22.0 3 25 25 1 1.00 1.00 41.44502
Golden Grahams G cold 110 1 1 280 0.0 15.0 9 45 25 2 1.00 0.75 23.80404
Cheerios G cold 110 6 2 290 2.0 17.0 1 105 25 1 1.00 1.25 50.76500
Corn Flakes K cold 100 2 0 290 1.0 21.0 2 35 25 1 1.00 1.00 45.86332
Rice Krispies K cold 110 2 0 290 0.0 22.0 3 35 25 1 1.00 1.00 40.56016
Product 19 K cold 100 3 0 320 1.0 20.0 3 45 100 3 1.00 1.00 41.50354

arrange()

We can arrange by multiple variables.

. . .

cereal |> 
  arrange(sodium, sugars) |>
  select(name, manuf, type, sodium, sugars)


name manuf type sodium sugars
Quaker Oatmeal Q hot 0 -1
Puffed Rice Q cold 0 0
Puffed Wheat Q cold 0 0
Shredded Wheat N cold 0 0
Shredded Wheat 'n'Bran N cold 0 0
Shredded Wheat spoon size N cold 0 0
Maypo A hot 0 3
Raisin Squares K cold 0 6
Frosted Mini-Wheats K cold 0 7
Strawberry Fruit Wheats N cold 15 5
100% Natural Bran Q cold 15 8
Golden Crisp P cold 45 15
Smacks K cold 70 15
Great Grains Pecan P cold 75 4
Cream of Wheat (Quick) N hot 80 0
Corn Pops K cold 90 12
Muesli Raisins; Dates; & Almonds R cold 95 11
Froot Loops K cold 125 13
Apple Jacks K cold 125 14
100% Bran N cold 130 6
Quaker Oat Squares Q cold 135 6
Fruity Pebbles P cold 135 12
All-Bran with Extra Fiber K cold 140 0
Grape Nuts Flakes P cold 140 5
Clusters G cold 140 7
Cracklin' Oat Bran K cold 140 7
Raisin Nut Bran G cold 140 8
Crispy Wheat & Raisins G cold 140 10
Trix G cold 140 12
Life Q cold 150 6
Muesli Raisins; Peaches; & Pecans R cold 150 11
Mueslix Crispy Blend K cold 150 13
Fruit & Fibre Dates; Walnuts; and Oats P cold 160 10
Nutri-grain Wheat K cold 170 2
Grape-Nuts P cold 170 3
Just Right Crunchy Nuggets K cold 170 6
Just Right Fruit & Nut K cold 170 9
Oatmeal Raisin Crisp G cold 170 10
Apple Cinnamon Cheerios G cold 180 10
Honey-comb P cold 180 11
Lucky Charms G cold 180 12
Cocoa Puffs G cold 180 13
Count Chocula G cold 180 13
Double Chex R cold 190 5
Nut&Honey Crunch K cold 190 9
Total Raisin Bran G cold 190 14
Total Corn Flakes G cold 200 3
Total Whole Grain G cold 200 3
Wheaties G cold 200 3
Bran Chex R cold 200 6
Almond Delight R cold 200 8
Wheaties Honey Gold G cold 200 8
Frosted Flakes K cold 200 11
Post Nat. Raisin Bran P cold 200 14
Bran Flakes P cold 210 5
Basic 4 G cold 210 8
Cinnamon Toast Crunch G cold 210 9
Raisin Bran K cold 210 12
Crispix K cold 220 3
Multi-Grain Cheerios G cold 220 6
Nutri-Grain Almond-Raisin K cold 220 7
Honey Graham Ohs Q cold 220 11
Cap'n'Crunch Q cold 220 12
Special K K cold 230 3
Wheat Chex R cold 230 3
Rice Chex R cold 240 2
Fruitful Bran K cold 240 12
Triples G cold 250 3
Honey Nut Cheerios G cold 250 10
Kix G cold 260 3
All-Bran K cold 260 5
Corn Chex R cold 280 3
Golden Grahams G cold 280 9
Cheerios G cold 290 1
Corn Flakes K cold 290 2
Rice Krispies K cold 290 3
Product 19 K cold 320 3

arrange(): Descending Order

Default is ascending order…

…but can add desc() to get descending order!

cereal |> 
  arrange(desc(sodium))

slice_max()

Selects the n rows with the maximum values of the specified variable.

cereal |> 
  slice_max(order_by = sugars, n = 3)
name manuf type calories protein fat sodium fiber carbo sugars potass vitamins shelf weight cups rating
Golden Crisp P cold 100 2 0 45 0 11 15 40 25 1 1.00 0.88 35.25244
Smacks K cold 110 2 1 70 1 9 15 40 25 2 1.00 0.75 31.23005
Apple Jacks K cold 110 2 0 125 1 11 14 30 25 2 1.00 1.00 33.17409
Post Nat. Raisin Bran P cold 120 3 1 200 6 11 14 260 25 3 1.33 0.67 37.84059
Total Raisin Bran G cold 140 3 1 190 4 15 14 230 100 3 1.50 1.00 28.59278

. . .

Not interested in ties?

You can use the with_ties = FALSE) argument to remove ties from your arrange()d output!

How do we “arrange” in base R?

You can use the order() function!


cereal[order(cereal$sodium, cereal$sugars),]
name manuf type calories protein fat sodium fiber carbo sugars potass vitamins shelf weight cups rating
58 Quaker Oatmeal Q hot 100 5 2 0 2.7 -1.0 -1 110 0 1 1.00 0.67 50.82839
55 Puffed Rice Q cold 50 1 0 0 0.0 13.0 0 15 0 3 0.50 1.00 60.75611
56 Puffed Wheat Q cold 50 2 0 0 1.0 10.0 0 50 0 3 0.50 1.00 63.00565
64 Shredded Wheat N cold 80 2 0 0 3.0 16.0 0 95 0 1 0.83 1.00 68.23588
65 Shredded Wheat 'n'Bran N cold 90 3 0 0 4.0 19.0 0 140 0 1 1.00 0.67 74.47295
66 Shredded Wheat spoon size N cold 90 3 0 0 3.0 20.0 0 120 0 1 1.00 0.67 72.80179
44 Maypo A hot 100 4 1 0 0.0 16.0 3 95 25 2 1.00 1.00 54.85092
61 Raisin Squares K cold 90 2 0 0 2.0 15.0 6 110 25 3 1.00 0.50 55.33314
27 Frosted Mini-Wheats K cold 100 3 0 0 3.0 14.0 7 100 25 2 1.00 0.80 58.34514
69 Strawberry Fruit Wheats N cold 90 2 0 15 3.0 15.0 5 90 25 2 1.00 1.00 59.36399
2 100% Natural Bran Q cold 120 3 5 15 2.0 8.0 8 135 0 3 1.00 1.00 33.98368
31 Golden Crisp P cold 100 2 0 45 0.0 11.0 15 40 25 1 1.00 0.88 35.25244
67 Smacks K cold 110 2 1 70 1.0 9.0 15 40 25 2 1.00 0.75 31.23005
35 Great Grains Pecan P cold 120 3 3 75 3.0 13.0 4 100 25 3 1.00 0.33 45.81172
21 Cream of Wheat (Quick) N hot 100 3 0 80 1.0 21.0 0 -1 0 2 1.00 1.00 64.53382
18 Corn Pops K cold 110 1 0 90 1.0 13.0 12 20 25 2 1.00 1.00 35.78279
45 Muesli Raisins; Dates; & Almonds R cold 150 4 3 95 3.0 16.0 11 170 25 3 1.00 1.00 37.13686
25 Froot Loops K cold 110 2 1 125 1.0 11.0 13 30 25 2 1.00 1.00 32.20758
7 Apple Jacks K cold 110 2 0 125 1.0 11.0 14 30 25 2 1.00 1.00 33.17409
1 100% Bran N cold 70 4 1 130 10.0 5.0 6 280 25 3 1.00 0.33 68.40297
57 Quaker Oat Squares Q cold 100 4 1 135 2.0 14.0 6 110 25 3 1.00 0.50 49.51187
30 Fruity Pebbles P cold 110 1 1 135 0.0 13.0 12 25 25 2 1.00 0.75 28.02576
4 All-Bran with Extra Fiber K cold 50 4 0 140 14.0 8.0 0 330 25 3 1.00 0.50 93.70491
33 Grape Nuts Flakes P cold 100 3 1 140 3.0 15.0 5 85 25 3 1.00 0.88 52.07690
14 Clusters G cold 110 3 2 140 2.0 13.0 7 105 25 3 1.00 0.50 40.40021
20 Cracklin' Oat Bran K cold 110 3 3 140 4.0 10.0 7 160 25 3 1.00 0.50 40.44877
60 Raisin Nut Bran G cold 100 3 2 140 2.5 10.5 8 140 25 3 1.00 0.50 39.70340
23 Crispy Wheat & Raisins G cold 100 2 1 140 2.0 11.0 10 120 25 3 1.00 0.75 36.17620
74 Trix G cold 110 1 1 140 0.0 13.0 12 25 25 2 1.00 1.00 27.75330
42 Life Q cold 100 4 2 150 2.0 12.0 6 95 25 2 1.00 0.67 45.32807
46 Muesli Raisins; Peaches; & Pecans R cold 150 4 3 150 3.0 16.0 11 170 25 3 1.00 1.00 34.13976
47 Mueslix Crispy Blend K cold 160 3 2 150 3.0 17.0 13 160 25 3 1.50 0.67 30.31335
28 Fruit & Fibre Dates; Walnuts; and Oats P cold 120 3 2 160 5.0 12.0 10 200 25 3 1.25 0.67 40.91705
51 Nutri-grain Wheat K cold 90 3 0 170 3.0 18.0 2 90 25 3 1.00 1.00 59.64284
34 Grape-Nuts P cold 110 3 0 170 3.0 17.0 3 90 25 3 1.00 0.25 53.37101
39 Just Right Crunchy Nuggets K cold 110 2 1 170 1.0 17.0 6 60 100 3 1.00 1.00 36.52368
40 Just Right Fruit & Nut K cold 140 3 1 170 2.0 20.0 9 95 100 3 1.30 0.75 36.47151
52 Oatmeal Raisin Crisp G cold 130 3 2 170 1.5 13.5 10 120 25 3 1.25 0.50 30.45084
6 Apple Cinnamon Cheerios G cold 110 2 2 180 1.5 10.5 10 70 25 1 1.00 0.75 29.50954
38 Honey-comb P cold 110 1 0 180 0.0 14.0 11 35 25 1 1.00 1.33 28.74241
43 Lucky Charms G cold 110 2 1 180 0.0 12.0 12 55 25 2 1.00 1.00 26.73451
15 Cocoa Puffs G cold 110 1 1 180 0.0 12.0 13 55 25 2 1.00 1.00 22.73645
19 Count Chocula G cold 110 1 1 180 0.0 12.0 13 65 25 2 1.00 1.00 22.39651
24 Double Chex R cold 100 2 0 190 1.0 18.0 5 80 25 3 1.00 0.75 44.33086
49 Nut&Honey Crunch K cold 120 2 1 190 0.0 15.0 9 40 25 2 1.00 0.67 29.92429
71 Total Raisin Bran G cold 140 3 1 190 4.0 15.0 14 230 100 3 1.50 1.00 28.59278
70 Total Corn Flakes G cold 110 2 1 200 0.0 21.0 3 35 100 3 1.00 1.00 38.83975
72 Total Whole Grain G cold 100 3 1 200 3.0 16.0 3 110 100 3 1.00 1.00 46.65884
76 Wheaties G cold 100 3 1 200 3.0 17.0 3 110 25 1 1.00 1.00 51.59219
9 Bran Chex R cold 90 2 1 200 4.0 15.0 6 125 25 1 1.00 0.67 49.12025
5 Almond Delight R cold 110 2 2 200 1.0 14.0 8 -1 25 3 1.00 0.75 34.38484
77 Wheaties Honey Gold G cold 110 2 1 200 1.0 16.0 8 60 25 1 1.00 0.75 36.18756
26 Frosted Flakes K cold 110 1 0 200 1.0 14.0 11 25 25 1 1.00 0.75 31.43597
53 Post Nat. Raisin Bran P cold 120 3 1 200 6.0 11.0 14 260 25 3 1.33 0.67 37.84059
10 Bran Flakes P cold 90 3 0 210 5.0 13.0 5 190 25 3 1.00 0.67 53.31381
8 Basic 4 G cold 130 3 2 210 2.0 18.0 8 100 25 3 1.33 0.75 37.03856
13 Cinnamon Toast Crunch G cold 120 1 3 210 0.0 13.0 9 45 25 2 1.00 0.75 19.82357
59 Raisin Bran K cold 120 3 1 210 5.0 14.0 12 240 25 2 1.33 0.75 39.25920
22 Crispix K cold 110 2 0 220 1.0 21.0 3 30 25 3 1.00 1.00 46.89564
48 Multi-Grain Cheerios G cold 100 2 1 220 2.0 15.0 6 90 25 1 1.00 1.00 40.10596
50 Nutri-Grain Almond-Raisin K cold 140 3 2 220 3.0 21.0 7 130 25 3 1.33 0.67 40.69232
36 Honey Graham Ohs Q cold 120 1 2 220 1.0 12.0 11 45 25 2 1.00 1.00 21.87129
11 Cap'n'Crunch Q cold 120 1 2 220 0.0 12.0 12 35 25 2 1.00 0.75 18.04285
68 Special K K cold 110 6 0 230 1.0 16.0 3 55 25 1 1.00 1.00 53.13132
75 Wheat Chex R cold 100 3 1 230 3.0 17.0 3 115 25 1 1.00 0.67 49.78744
62 Rice Chex R cold 110 1 0 240 0.0 23.0 2 30 25 1 1.00 1.13 41.99893
29 Fruitful Bran K cold 120 3 0 240 5.0 14.0 12 190 25 3 1.33 0.67 41.01549
73 Triples G cold 110 2 1 250 0.0 21.0 3 60 25 3 1.00 0.75 39.10617
37 Honey Nut Cheerios G cold 110 3 1 250 1.5 11.5 10 90 25 1 1.00 0.75 31.07222
41 Kix G cold 110 2 1 260 0.0 21.0 3 40 25 2 1.00 1.50 39.24111
3 All-Bran K cold 70 4 1 260 9.0 7.0 5 320 25 3 1.00 0.33 59.42551
16 Corn Chex R cold 110 2 0 280 0.0 22.0 3 25 25 1 1.00 1.00 41.44502
32 Golden Grahams G cold 110 1 1 280 0.0 15.0 9 45 25 2 1.00 0.75 23.80404
12 Cheerios G cold 110 6 2 290 2.0 17.0 1 105 25 1 1.00 1.25 50.76500
17 Corn Flakes K cold 100 2 0 290 1.0 21.0 2 35 25 1 1.00 1.00 45.86332
63 Rice Krispies K cold 110 2 0 290 0.0 22.0 3 35 25 1 1.00 1.00 40.56016
54 Product 19 K cold 100 3 0 320 1.0 20.0 3 45 100 3 1.00 1.00 41.50354

select()

select()

We select which variables (columns) we would like to remain in the data.

. . .

cereal |> 
  select(name, manuf, calories, cups)
name manuf calories cups
100% Bran N 70 0.33
100% Natural Bran Q 120 1.00
All-Bran K 70 0.33
All-Bran with Extra Fiber K 50 0.50
Almond Delight R 110 0.75
Apple Cinnamon Cheerios G 110 0.75
Apple Jacks K 110 1.00
Basic 4 G 130 0.75
Bran Chex R 90 0.67
Bran Flakes P 90 0.67
Cap'n'Crunch Q 120 0.75
Cheerios G 110 1.25
Cinnamon Toast Crunch G 120 0.75
Clusters G 110 0.50
Cocoa Puffs G 110 1.00
Corn Chex R 110 1.00
Corn Flakes K 100 1.00
Corn Pops K 110 1.00
Count Chocula G 110 1.00
Cracklin' Oat Bran K 110 0.50
Cream of Wheat (Quick) N 100 1.00
Crispix K 110 1.00
Crispy Wheat & Raisins G 100 0.75
Double Chex R 100 0.75
Froot Loops K 110 1.00
Frosted Flakes K 110 0.75
Frosted Mini-Wheats K 100 0.80
Fruit & Fibre Dates; Walnuts; and Oats P 120 0.67
Fruitful Bran K 120 0.67
Fruity Pebbles P 110 0.75
Golden Crisp P 100 0.88
Golden Grahams G 110 0.75
Grape Nuts Flakes P 100 0.88
Grape-Nuts P 110 0.25
Great Grains Pecan P 120 0.33
Honey Graham Ohs Q 120 1.00
Honey Nut Cheerios G 110 0.75
Honey-comb P 110 1.33
Just Right Crunchy Nuggets K 110 1.00
Just Right Fruit & Nut K 140 0.75
Kix G 110 1.50
Life Q 100 0.67
Lucky Charms G 110 1.00
Maypo A 100 1.00
Muesli Raisins; Dates; & Almonds R 150 1.00
Muesli Raisins; Peaches; & Pecans R 150 1.00
Mueslix Crispy Blend K 160 0.67
Multi-Grain Cheerios G 100 1.00
Nut&Honey Crunch K 120 0.67
Nutri-Grain Almond-Raisin K 140 0.67
Nutri-grain Wheat K 90 1.00
Oatmeal Raisin Crisp G 130 0.50
Post Nat. Raisin Bran P 120 0.67
Product 19 K 100 1.00
Puffed Rice Q 50 1.00
Puffed Wheat Q 50 1.00
Quaker Oat Squares Q 100 0.50
Quaker Oatmeal Q 100 0.67
Raisin Bran K 120 0.75
Raisin Nut Bran G 100 0.50
Raisin Squares K 90 0.50
Rice Chex R 110 1.13
Rice Krispies K 110 1.00
Shredded Wheat N 80 1.00
Shredded Wheat 'n'Bran N 90 0.67
Shredded Wheat spoon size N 90 0.67
Smacks K 110 0.75
Special K K 110 1.00
Strawberry Fruit Wheats N 90 1.00
Total Corn Flakes G 110 1.00
Total Raisin Bran G 140 1.00
Total Whole Grain G 100 1.00
Triples G 110 0.75
Trix G 110 1.00
Wheat Chex R 100 0.67
Wheaties G 100 1.00
Wheaties Honey Gold G 110 0.75

select() a Sequence of Columns

cereal |> 
  select(name:calories)


name manuf type calories
100% Bran N cold 70
100% Natural Bran Q cold 120
All-Bran K cold 70
All-Bran with Extra Fiber K cold 50
Almond Delight R cold 110
Apple Cinnamon Cheerios G cold 110
Apple Jacks K cold 110
Basic 4 G cold 130
Bran Chex R cold 90
Bran Flakes P cold 90
Cap'n'Crunch Q cold 120
Cheerios G cold 110
Cinnamon Toast Crunch G cold 120
Clusters G cold 110
Cocoa Puffs G cold 110
Corn Chex R cold 110
Corn Flakes K cold 100
Corn Pops K cold 110
Count Chocula G cold 110
Cracklin' Oat Bran K cold 110
Cream of Wheat (Quick) N hot 100
Crispix K cold 110
Crispy Wheat & Raisins G cold 100
Double Chex R cold 100
Froot Loops K cold 110
Frosted Flakes K cold 110
Frosted Mini-Wheats K cold 100
Fruit & Fibre Dates; Walnuts; and Oats P cold 120
Fruitful Bran K cold 120
Fruity Pebbles P cold 110
Golden Crisp P cold 100
Golden Grahams G cold 110
Grape Nuts Flakes P cold 100
Grape-Nuts P cold 110
Great Grains Pecan P cold 120
Honey Graham Ohs Q cold 120
Honey Nut Cheerios G cold 110
Honey-comb P cold 110
Just Right Crunchy Nuggets K cold 110
Just Right Fruit & Nut K cold 140
Kix G cold 110
Life Q cold 100
Lucky Charms G cold 110
Maypo A hot 100
Muesli Raisins; Dates; & Almonds R cold 150
Muesli Raisins; Peaches; & Pecans R cold 150
Mueslix Crispy Blend K cold 160
Multi-Grain Cheerios G cold 100
Nut&Honey Crunch K cold 120
Nutri-Grain Almond-Raisin K cold 140
Nutri-grain Wheat K cold 90
Oatmeal Raisin Crisp G cold 130
Post Nat. Raisin Bran P cold 120
Product 19 K cold 100
Puffed Rice Q cold 50
Puffed Wheat Q cold 50
Quaker Oat Squares Q cold 100
Quaker Oatmeal Q hot 100
Raisin Bran K cold 120
Raisin Nut Bran G cold 100
Raisin Squares K cold 90
Rice Chex R cold 110
Rice Krispies K cold 110
Shredded Wheat N cold 80
Shredded Wheat 'n'Bran N cold 90
Shredded Wheat spoon size N cold 90
Smacks K cold 110
Special K K cold 110
Strawberry Fruit Wheats N cold 90
Total Corn Flakes G cold 110
Total Raisin Bran G cold 140
Total Whole Grain G cold 100
Triples G cold 110
Trix G cold 110
Wheat Chex R cold 100
Wheaties G cold 100
Wheaties Honey Gold G cold 110

Remove Columns

cereal |> 
  select(-rating)


name manuf type calories protein fat sodium fiber carbo sugars potass vitamins shelf weight cups
100% Bran N cold 70 4 1 130 10.0 5.0 6 280 25 3 1.00 0.33
100% Natural Bran Q cold 120 3 5 15 2.0 8.0 8 135 0 3 1.00 1.00
All-Bran K cold 70 4 1 260 9.0 7.0 5 320 25 3 1.00 0.33
All-Bran with Extra Fiber K cold 50 4 0 140 14.0 8.0 0 330 25 3 1.00 0.50
Almond Delight R cold 110 2 2 200 1.0 14.0 8 -1 25 3 1.00 0.75
Apple Cinnamon Cheerios G cold 110 2 2 180 1.5 10.5 10 70 25 1 1.00 0.75
Apple Jacks K cold 110 2 0 125 1.0 11.0 14 30 25 2 1.00 1.00
Basic 4 G cold 130 3 2 210 2.0 18.0 8 100 25 3 1.33 0.75
Bran Chex R cold 90 2 1 200 4.0 15.0 6 125 25 1 1.00 0.67
Bran Flakes P cold 90 3 0 210 5.0 13.0 5 190 25 3 1.00 0.67
Cap'n'Crunch Q cold 120 1 2 220 0.0 12.0 12 35 25 2 1.00 0.75
Cheerios G cold 110 6 2 290 2.0 17.0 1 105 25 1 1.00 1.25
Cinnamon Toast Crunch G cold 120 1 3 210 0.0 13.0 9 45 25 2 1.00 0.75
Clusters G cold 110 3 2 140 2.0 13.0 7 105 25 3 1.00 0.50
Cocoa Puffs G cold 110 1 1 180 0.0 12.0 13 55 25 2 1.00 1.00
Corn Chex R cold 110 2 0 280 0.0 22.0 3 25 25 1 1.00 1.00
Corn Flakes K cold 100 2 0 290 1.0 21.0 2 35 25 1 1.00 1.00
Corn Pops K cold 110 1 0 90 1.0 13.0 12 20 25 2 1.00 1.00
Count Chocula G cold 110 1 1 180 0.0 12.0 13 65 25 2 1.00 1.00
Cracklin' Oat Bran K cold 110 3 3 140 4.0 10.0 7 160 25 3 1.00 0.50
Cream of Wheat (Quick) N hot 100 3 0 80 1.0 21.0 0 -1 0 2 1.00 1.00
Crispix K cold 110 2 0 220 1.0 21.0 3 30 25 3 1.00 1.00
Crispy Wheat & Raisins G cold 100 2 1 140 2.0 11.0 10 120 25 3 1.00 0.75
Double Chex R cold 100 2 0 190 1.0 18.0 5 80 25 3 1.00 0.75
Froot Loops K cold 110 2 1 125 1.0 11.0 13 30 25 2 1.00 1.00
Frosted Flakes K cold 110 1 0 200 1.0 14.0 11 25 25 1 1.00 0.75
Frosted Mini-Wheats K cold 100 3 0 0 3.0 14.0 7 100 25 2 1.00 0.80
Fruit & Fibre Dates; Walnuts; and Oats P cold 120 3 2 160 5.0 12.0 10 200 25 3 1.25 0.67
Fruitful Bran K cold 120 3 0 240 5.0 14.0 12 190 25 3 1.33 0.67
Fruity Pebbles P cold 110 1 1 135 0.0 13.0 12 25 25 2 1.00 0.75
Golden Crisp P cold 100 2 0 45 0.0 11.0 15 40 25 1 1.00 0.88
Golden Grahams G cold 110 1 1 280 0.0 15.0 9 45 25 2 1.00 0.75
Grape Nuts Flakes P cold 100 3 1 140 3.0 15.0 5 85 25 3 1.00 0.88
Grape-Nuts P cold 110 3 0 170 3.0 17.0 3 90 25 3 1.00 0.25
Great Grains Pecan P cold 120 3 3 75 3.0 13.0 4 100 25 3 1.00 0.33
Honey Graham Ohs Q cold 120 1 2 220 1.0 12.0 11 45 25 2 1.00 1.00
Honey Nut Cheerios G cold 110 3 1 250 1.5 11.5 10 90 25 1 1.00 0.75
Honey-comb P cold 110 1 0 180 0.0 14.0 11 35 25 1 1.00 1.33
Just Right Crunchy Nuggets K cold 110 2 1 170 1.0 17.0 6 60 100 3 1.00 1.00
Just Right Fruit & Nut K cold 140 3 1 170 2.0 20.0 9 95 100 3 1.30 0.75
Kix G cold 110 2 1 260 0.0 21.0 3 40 25 2 1.00 1.50
Life Q cold 100 4 2 150 2.0 12.0 6 95 25 2 1.00 0.67
Lucky Charms G cold 110 2 1 180 0.0 12.0 12 55 25 2 1.00 1.00
Maypo A hot 100 4 1 0 0.0 16.0 3 95 25 2 1.00 1.00
Muesli Raisins; Dates; & Almonds R cold 150 4 3 95 3.0 16.0 11 170 25 3 1.00 1.00
Muesli Raisins; Peaches; & Pecans R cold 150 4 3 150 3.0 16.0 11 170 25 3 1.00 1.00
Mueslix Crispy Blend K cold 160 3 2 150 3.0 17.0 13 160 25 3 1.50 0.67
Multi-Grain Cheerios G cold 100 2 1 220 2.0 15.0 6 90 25 1 1.00 1.00
Nut&Honey Crunch K cold 120 2 1 190 0.0 15.0 9 40 25 2 1.00 0.67
Nutri-Grain Almond-Raisin K cold 140 3 2 220 3.0 21.0 7 130 25 3 1.33 0.67
Nutri-grain Wheat K cold 90 3 0 170 3.0 18.0 2 90 25 3 1.00 1.00
Oatmeal Raisin Crisp G cold 130 3 2 170 1.5 13.5 10 120 25 3 1.25 0.50
Post Nat. Raisin Bran P cold 120 3 1 200 6.0 11.0 14 260 25 3 1.33 0.67
Product 19 K cold 100 3 0 320 1.0 20.0 3 45 100 3 1.00 1.00
Puffed Rice Q cold 50 1 0 0 0.0 13.0 0 15 0 3 0.50 1.00
Puffed Wheat Q cold 50 2 0 0 1.0 10.0 0 50 0 3 0.50 1.00
Quaker Oat Squares Q cold 100 4 1 135 2.0 14.0 6 110 25 3 1.00 0.50
Quaker Oatmeal Q hot 100 5 2 0 2.7 -1.0 -1 110 0 1 1.00 0.67
Raisin Bran K cold 120 3 1 210 5.0 14.0 12 240 25 2 1.33 0.75
Raisin Nut Bran G cold 100 3 2 140 2.5 10.5 8 140 25 3 1.00 0.50
Raisin Squares K cold 90 2 0 0 2.0 15.0 6 110 25 3 1.00 0.50
Rice Chex R cold 110 1 0 240 0.0 23.0 2 30 25 1 1.00 1.13
Rice Krispies K cold 110 2 0 290 0.0 22.0 3 35 25 1 1.00 1.00
Shredded Wheat N cold 80 2 0 0 3.0 16.0 0 95 0 1 0.83 1.00
Shredded Wheat 'n'Bran N cold 90 3 0 0 4.0 19.0 0 140 0 1 1.00 0.67
Shredded Wheat spoon size N cold 90 3 0 0 3.0 20.0 0 120 0 1 1.00 0.67
Smacks K cold 110 2 1 70 1.0 9.0 15 40 25 2 1.00 0.75
Special K K cold 110 6 0 230 1.0 16.0 3 55 25 1 1.00 1.00
Strawberry Fruit Wheats N cold 90 2 0 15 3.0 15.0 5 90 25 2 1.00 1.00
Total Corn Flakes G cold 110 2 1 200 0.0 21.0 3 35 100 3 1.00 1.00
Total Raisin Bran G cold 140 3 1 190 4.0 15.0 14 230 100 3 1.50 1.00
Total Whole Grain G cold 100 3 1 200 3.0 16.0 3 110 100 3 1.00 1.00
Triples G cold 110 2 1 250 0.0 21.0 3 60 25 3 1.00 0.75
Trix G cold 110 1 1 140 0.0 13.0 12 25 25 2 1.00 1.00
Wheat Chex R cold 100 3 1 230 3.0 17.0 3 115 25 1 1.00 0.67
Wheaties G cold 100 3 1 200 3.0 17.0 3 110 25 1 1.00 1.00
Wheaties Honey Gold G cold 110 2 1 200 1.0 16.0 8 60 25 1 1.00 0.75

select(): Reordering

You can reorder columns inside of select().

cereal |> 
  select(name, rating, manuf, type, 
         calories, cups, weight,
         everything()
         )
name rating manuf type calories cups weight protein fat sodium fiber carbo sugars potass vitamins shelf
100% Bran 68.40297 N cold 70 0.33 1.00 4 1 130 10.0 5.0 6 280 25 3
100% Natural Bran 33.98368 Q cold 120 1.00 1.00 3 5 15 2.0 8.0 8 135 0 3
All-Bran 59.42551 K cold 70 0.33 1.00 4 1 260 9.0 7.0 5 320 25 3
All-Bran with Extra Fiber 93.70491 K cold 50 0.50 1.00 4 0 140 14.0 8.0 0 330 25 3
Almond Delight 34.38484 R cold 110 0.75 1.00 2 2 200 1.0 14.0 8 -1 25 3
Apple Cinnamon Cheerios 29.50954 G cold 110 0.75 1.00 2 2 180 1.5 10.5 10 70 25 1
Apple Jacks 33.17409 K cold 110 1.00 1.00 2 0 125 1.0 11.0 14 30 25 2
Basic 4 37.03856 G cold 130 0.75 1.33 3 2 210 2.0 18.0 8 100 25 3
Bran Chex 49.12025 R cold 90 0.67 1.00 2 1 200 4.0 15.0 6 125 25 1
Bran Flakes 53.31381 P cold 90 0.67 1.00 3 0 210 5.0 13.0 5 190 25 3
Cap'n'Crunch 18.04285 Q cold 120 0.75 1.00 1 2 220 0.0 12.0 12 35 25 2
Cheerios 50.76500 G cold 110 1.25 1.00 6 2 290 2.0 17.0 1 105 25 1
Cinnamon Toast Crunch 19.82357 G cold 120 0.75 1.00 1 3 210 0.0 13.0 9 45 25 2
Clusters 40.40021 G cold 110 0.50 1.00 3 2 140 2.0 13.0 7 105 25 3
Cocoa Puffs 22.73645 G cold 110 1.00 1.00 1 1 180 0.0 12.0 13 55 25 2
Corn Chex 41.44502 R cold 110 1.00 1.00 2 0 280 0.0 22.0 3 25 25 1
Corn Flakes 45.86332 K cold 100 1.00 1.00 2 0 290 1.0 21.0 2 35 25 1
Corn Pops 35.78279 K cold 110 1.00 1.00 1 0 90 1.0 13.0 12 20 25 2
Count Chocula 22.39651 G cold 110 1.00 1.00 1 1 180 0.0 12.0 13 65 25 2
Cracklin' Oat Bran 40.44877 K cold 110 0.50 1.00 3 3 140 4.0 10.0 7 160 25 3
Cream of Wheat (Quick) 64.53382 N hot 100 1.00 1.00 3 0 80 1.0 21.0 0 -1 0 2
Crispix 46.89564 K cold 110 1.00 1.00 2 0 220 1.0 21.0 3 30 25 3
Crispy Wheat & Raisins 36.17620 G cold 100 0.75 1.00 2 1 140 2.0 11.0 10 120 25 3
Double Chex 44.33086 R cold 100 0.75 1.00 2 0 190 1.0 18.0 5 80 25 3
Froot Loops 32.20758 K cold 110 1.00 1.00 2 1 125 1.0 11.0 13 30 25 2
Frosted Flakes 31.43597 K cold 110 0.75 1.00 1 0 200 1.0 14.0 11 25 25 1
Frosted Mini-Wheats 58.34514 K cold 100 0.80 1.00 3 0 0 3.0 14.0 7 100 25 2
Fruit & Fibre Dates; Walnuts; and Oats 40.91705 P cold 120 0.67 1.25 3 2 160 5.0 12.0 10 200 25 3
Fruitful Bran 41.01549 K cold 120 0.67 1.33 3 0 240 5.0 14.0 12 190 25 3
Fruity Pebbles 28.02576 P cold 110 0.75 1.00 1 1 135 0.0 13.0 12 25 25 2
Golden Crisp 35.25244 P cold 100 0.88 1.00 2 0 45 0.0 11.0 15 40 25 1
Golden Grahams 23.80404 G cold 110 0.75 1.00 1 1 280 0.0 15.0 9 45 25 2
Grape Nuts Flakes 52.07690 P cold 100 0.88 1.00 3 1 140 3.0 15.0 5 85 25 3
Grape-Nuts 53.37101 P cold 110 0.25 1.00 3 0 170 3.0 17.0 3 90 25 3
Great Grains Pecan 45.81172 P cold 120 0.33 1.00 3 3 75 3.0 13.0 4 100 25 3
Honey Graham Ohs 21.87129 Q cold 120 1.00 1.00 1 2 220 1.0 12.0 11 45 25 2
Honey Nut Cheerios 31.07222 G cold 110 0.75 1.00 3 1 250 1.5 11.5 10 90 25 1
Honey-comb 28.74241 P cold 110 1.33 1.00 1 0 180 0.0 14.0 11 35 25 1
Just Right Crunchy Nuggets 36.52368 K cold 110 1.00 1.00 2 1 170 1.0 17.0 6 60 100 3
Just Right Fruit & Nut 36.47151 K cold 140 0.75 1.30 3 1 170 2.0 20.0 9 95 100 3
Kix 39.24111 G cold 110 1.50 1.00 2 1 260 0.0 21.0 3 40 25 2
Life 45.32807 Q cold 100 0.67 1.00 4 2 150 2.0 12.0 6 95 25 2
Lucky Charms 26.73451 G cold 110 1.00 1.00 2 1 180 0.0 12.0 12 55 25 2
Maypo 54.85092 A hot 100 1.00 1.00 4 1 0 0.0 16.0 3 95 25 2
Muesli Raisins; Dates; & Almonds 37.13686 R cold 150 1.00 1.00 4 3 95 3.0 16.0 11 170 25 3
Muesli Raisins; Peaches; & Pecans 34.13976 R cold 150 1.00 1.00 4 3 150 3.0 16.0 11 170 25 3
Mueslix Crispy Blend 30.31335 K cold 160 0.67 1.50 3 2 150 3.0 17.0 13 160 25 3
Multi-Grain Cheerios 40.10596 G cold 100 1.00 1.00 2 1 220 2.0 15.0 6 90 25 1
Nut&Honey Crunch 29.92429 K cold 120 0.67 1.00 2 1 190 0.0 15.0 9 40 25 2
Nutri-Grain Almond-Raisin 40.69232 K cold 140 0.67 1.33 3 2 220 3.0 21.0 7 130 25 3
Nutri-grain Wheat 59.64284 K cold 90 1.00 1.00 3 0 170 3.0 18.0 2 90 25 3
Oatmeal Raisin Crisp 30.45084 G cold 130 0.50 1.25 3 2 170 1.5 13.5 10 120 25 3
Post Nat. Raisin Bran 37.84059 P cold 120 0.67 1.33 3 1 200 6.0 11.0 14 260 25 3
Product 19 41.50354 K cold 100 1.00 1.00 3 0 320 1.0 20.0 3 45 100 3
Puffed Rice 60.75611 Q cold 50 1.00 0.50 1 0 0 0.0 13.0 0 15 0 3
Puffed Wheat 63.00565 Q cold 50 1.00 0.50 2 0 0 1.0 10.0 0 50 0 3
Quaker Oat Squares 49.51187 Q cold 100 0.50 1.00 4 1 135 2.0 14.0 6 110 25 3
Quaker Oatmeal 50.82839 Q hot 100 0.67 1.00 5 2 0 2.7 -1.0 -1 110 0 1
Raisin Bran 39.25920 K cold 120 0.75 1.33 3 1 210 5.0 14.0 12 240 25 2
Raisin Nut Bran 39.70340 G cold 100 0.50 1.00 3 2 140 2.5 10.5 8 140 25 3
Raisin Squares 55.33314 K cold 90 0.50 1.00 2 0 0 2.0 15.0 6 110 25 3
Rice Chex 41.99893 R cold 110 1.13 1.00 1 0 240 0.0 23.0 2 30 25 1
Rice Krispies 40.56016 K cold 110 1.00 1.00 2 0 290 0.0 22.0 3 35 25 1
Shredded Wheat 68.23588 N cold 80 1.00 0.83 2 0 0 3.0 16.0 0 95 0 1
Shredded Wheat 'n'Bran 74.47295 N cold 90 0.67 1.00 3 0 0 4.0 19.0 0 140 0 1
Shredded Wheat spoon size 72.80179 N cold 90 0.67 1.00 3 0 0 3.0 20.0 0 120 0 1
Smacks 31.23005 K cold 110 0.75 1.00 2 1 70 1.0 9.0 15 40 25 2
Special K 53.13132 K cold 110 1.00 1.00 6 0 230 1.0 16.0 3 55 25 1
Strawberry Fruit Wheats 59.36399 N cold 90 1.00 1.00 2 0 15 3.0 15.0 5 90 25 2
Total Corn Flakes 38.83975 G cold 110 1.00 1.00 2 1 200 0.0 21.0 3 35 100 3
Total Raisin Bran 28.59278 G cold 140 1.00 1.50 3 1 190 4.0 15.0 14 230 100 3
Total Whole Grain 46.65884 G cold 100 1.00 1.00 3 1 200 3.0 16.0 3 110 100 3
Triples 39.10617 G cold 110 0.75 1.00 2 1 250 0.0 21.0 3 60 25 3
Trix 27.75330 G cold 110 1.00 1.00 1 1 140 0.0 13.0 12 25 25 2
Wheat Chex 49.78744 R cold 100 0.67 1.00 3 1 230 3.0 17.0 3 115 25 1
Wheaties 51.59219 G cold 100 1.00 1.00 3 1 200 3.0 17.0 3 110 25 1
Wheaties Honey Gold 36.18756 G cold 110 0.75 1.00 2 1 200 1.0 16.0 8 60 25 1

select(): Handy Helpers!

  • everything() : selects all columns that you have not already specified
  • starts_with() : selects columns with names that start with the specified string
  • ends_with() : selects columns with names that end with the specified string
  • contains() : selects columns with names that contain the specified string

rename()

Header text: 'dplyr:: rename() - rename columns'. Below, an illustration of a mouse standing on a wedge of swiss cheese, changing column names from 'species' to 'nemesis,' and 'site' to 'lair.' On a cork board next to the mouse are images of 'Cheese thieves' suspects (narwhal, chicken and pika) and maps of their locations.

rename()

  • You can rename columns with select(), but all columns not specified will be dropped.
    • Using the rename() function is easier!
cereal |> 
  rename(temp = type)
name manuf temp calories protein fat sodium fiber carbo sugars potass vitamins shelf weight cups rating
100% Bran N cold 70 4 1 130 10.0 5.0 6 280 25 3 1.00 0.33 68.40297
100% Natural Bran Q cold 120 3 5 15 2.0 8.0 8 135 0 3 1.00 1.00 33.98368
All-Bran K cold 70 4 1 260 9.0 7.0 5 320 25 3 1.00 0.33 59.42551
All-Bran with Extra Fiber K cold 50 4 0 140 14.0 8.0 0 330 25 3 1.00 0.50 93.70491
Almond Delight R cold 110 2 2 200 1.0 14.0 8 -1 25 3 1.00 0.75 34.38484
Apple Cinnamon Cheerios G cold 110 2 2 180 1.5 10.5 10 70 25 1 1.00 0.75 29.50954
Apple Jacks K cold 110 2 0 125 1.0 11.0 14 30 25 2 1.00 1.00 33.17409
Basic 4 G cold 130 3 2 210 2.0 18.0 8 100 25 3 1.33 0.75 37.03856
Bran Chex R cold 90 2 1 200 4.0 15.0 6 125 25 1 1.00 0.67 49.12025
Bran Flakes P cold 90 3 0 210 5.0 13.0 5 190 25 3 1.00 0.67 53.31381
Cap'n'Crunch Q cold 120 1 2 220 0.0 12.0 12 35 25 2 1.00 0.75 18.04285
Cheerios G cold 110 6 2 290 2.0 17.0 1 105 25 1 1.00 1.25 50.76500
Cinnamon Toast Crunch G cold 120 1 3 210 0.0 13.0 9 45 25 2 1.00 0.75 19.82357
Clusters G cold 110 3 2 140 2.0 13.0 7 105 25 3 1.00 0.50 40.40021
Cocoa Puffs G cold 110 1 1 180 0.0 12.0 13 55 25 2 1.00 1.00 22.73645
Corn Chex R cold 110 2 0 280 0.0 22.0 3 25 25 1 1.00 1.00 41.44502
Corn Flakes K cold 100 2 0 290 1.0 21.0 2 35 25 1 1.00 1.00 45.86332
Corn Pops K cold 110 1 0 90 1.0 13.0 12 20 25 2 1.00 1.00 35.78279
Count Chocula G cold 110 1 1 180 0.0 12.0 13 65 25 2 1.00 1.00 22.39651
Cracklin' Oat Bran K cold 110 3 3 140 4.0 10.0 7 160 25 3 1.00 0.50 40.44877
Cream of Wheat (Quick) N hot 100 3 0 80 1.0 21.0 0 -1 0 2 1.00 1.00 64.53382
Crispix K cold 110 2 0 220 1.0 21.0 3 30 25 3 1.00 1.00 46.89564
Crispy Wheat & Raisins G cold 100 2 1 140 2.0 11.0 10 120 25 3 1.00 0.75 36.17620
Double Chex R cold 100 2 0 190 1.0 18.0 5 80 25 3 1.00 0.75 44.33086
Froot Loops K cold 110 2 1 125 1.0 11.0 13 30 25 2 1.00 1.00 32.20758
Frosted Flakes K cold 110 1 0 200 1.0 14.0 11 25 25 1 1.00 0.75 31.43597
Frosted Mini-Wheats K cold 100 3 0 0 3.0 14.0 7 100 25 2 1.00 0.80 58.34514
Fruit & Fibre Dates; Walnuts; and Oats P cold 120 3 2 160 5.0 12.0 10 200 25 3 1.25 0.67 40.91705
Fruitful Bran K cold 120 3 0 240 5.0 14.0 12 190 25 3 1.33 0.67 41.01549
Fruity Pebbles P cold 110 1 1 135 0.0 13.0 12 25 25 2 1.00 0.75 28.02576
Golden Crisp P cold 100 2 0 45 0.0 11.0 15 40 25 1 1.00 0.88 35.25244
Golden Grahams G cold 110 1 1 280 0.0 15.0 9 45 25 2 1.00 0.75 23.80404
Grape Nuts Flakes P cold 100 3 1 140 3.0 15.0 5 85 25 3 1.00 0.88 52.07690
Grape-Nuts P cold 110 3 0 170 3.0 17.0 3 90 25 3 1.00 0.25 53.37101
Great Grains Pecan P cold 120 3 3 75 3.0 13.0 4 100 25 3 1.00 0.33 45.81172
Honey Graham Ohs Q cold 120 1 2 220 1.0 12.0 11 45 25 2 1.00 1.00 21.87129
Honey Nut Cheerios G cold 110 3 1 250 1.5 11.5 10 90 25 1 1.00 0.75 31.07222
Honey-comb P cold 110 1 0 180 0.0 14.0 11 35 25 1 1.00 1.33 28.74241
Just Right Crunchy Nuggets K cold 110 2 1 170 1.0 17.0 6 60 100 3 1.00 1.00 36.52368
Just Right Fruit & Nut K cold 140 3 1 170 2.0 20.0 9 95 100 3 1.30 0.75 36.47151
Kix G cold 110 2 1 260 0.0 21.0 3 40 25 2 1.00 1.50 39.24111
Life Q cold 100 4 2 150 2.0 12.0 6 95 25 2 1.00 0.67 45.32807
Lucky Charms G cold 110 2 1 180 0.0 12.0 12 55 25 2 1.00 1.00 26.73451
Maypo A hot 100 4 1 0 0.0 16.0 3 95 25 2 1.00 1.00 54.85092
Muesli Raisins; Dates; & Almonds R cold 150 4 3 95 3.0 16.0 11 170 25 3 1.00 1.00 37.13686
Muesli Raisins; Peaches; & Pecans R cold 150 4 3 150 3.0 16.0 11 170 25 3 1.00 1.00 34.13976
Mueslix Crispy Blend K cold 160 3 2 150 3.0 17.0 13 160 25 3 1.50 0.67 30.31335
Multi-Grain Cheerios G cold 100 2 1 220 2.0 15.0 6 90 25 1 1.00 1.00 40.10596
Nut&Honey Crunch K cold 120 2 1 190 0.0 15.0 9 40 25 2 1.00 0.67 29.92429
Nutri-Grain Almond-Raisin K cold 140 3 2 220 3.0 21.0 7 130 25 3 1.33 0.67 40.69232
Nutri-grain Wheat K cold 90 3 0 170 3.0 18.0 2 90 25 3 1.00 1.00 59.64284
Oatmeal Raisin Crisp G cold 130 3 2 170 1.5 13.5 10 120 25 3 1.25 0.50 30.45084
Post Nat. Raisin Bran P cold 120 3 1 200 6.0 11.0 14 260 25 3 1.33 0.67 37.84059
Product 19 K cold 100 3 0 320 1.0 20.0 3 45 100 3 1.00 1.00 41.50354
Puffed Rice Q cold 50 1 0 0 0.0 13.0 0 15 0 3 0.50 1.00 60.75611
Puffed Wheat Q cold 50 2 0 0 1.0 10.0 0 50 0 3 0.50 1.00 63.00565
Quaker Oat Squares Q cold 100 4 1 135 2.0 14.0 6 110 25 3 1.00 0.50 49.51187
Quaker Oatmeal Q hot 100 5 2 0 2.7 -1.0 -1 110 0 1 1.00 0.67 50.82839
Raisin Bran K cold 120 3 1 210 5.0 14.0 12 240 25 2 1.33 0.75 39.25920
Raisin Nut Bran G cold 100 3 2 140 2.5 10.5 8 140 25 3 1.00 0.50 39.70340
Raisin Squares K cold 90 2 0 0 2.0 15.0 6 110 25 3 1.00 0.50 55.33314
Rice Chex R cold 110 1 0 240 0.0 23.0 2 30 25 1 1.00 1.13 41.99893
Rice Krispies K cold 110 2 0 290 0.0 22.0 3 35 25 1 1.00 1.00 40.56016
Shredded Wheat N cold 80 2 0 0 3.0 16.0 0 95 0 1 0.83 1.00 68.23588
Shredded Wheat 'n'Bran N cold 90 3 0 0 4.0 19.0 0 140 0 1 1.00 0.67 74.47295
Shredded Wheat spoon size N cold 90 3 0 0 3.0 20.0 0 120 0 1 1.00 0.67 72.80179
Smacks K cold 110 2 1 70 1.0 9.0 15 40 25 2 1.00 0.75 31.23005
Special K K cold 110 6 0 230 1.0 16.0 3 55 25 1 1.00 1.00 53.13132
Strawberry Fruit Wheats N cold 90 2 0 15 3.0 15.0 5 90 25 2 1.00 1.00 59.36399
Total Corn Flakes G cold 110 2 1 200 0.0 21.0 3 35 100 3 1.00 1.00 38.83975
Total Raisin Bran G cold 140 3 1 190 4.0 15.0 14 230 100 3 1.50 1.00 28.59278
Total Whole Grain G cold 100 3 1 200 3.0 16.0 3 110 100 3 1.00 1.00 46.65884
Triples G cold 110 2 1 250 0.0 21.0 3 60 25 3 1.00 0.75 39.10617
Trix G cold 110 1 1 140 0.0 13.0 12 25 25 2 1.00 1.00 27.75330
Wheat Chex R cold 100 3 1 230 3.0 17.0 3 115 25 1 1.00 0.67 49.78744
Wheaties G cold 100 3 1 200 3.0 17.0 3 110 25 1 1.00 1.00 51.59219
Wheaties Honey Gold G cold 110 2 1 200 1.0 16.0 8 60 25 1 1.00 0.75 36.18756

How do we “select” in base R?

You can use bracketing ([]) or the subset() function!

cereal[ , c("name", 
            "manuf", 
            "calories", 
            "cups")]
subset(cereal, 
       select = c(name, 
                  manuf, 
                  calories, 
                  cups)
       )
name manuf calories cups
100% Bran N 70 0.33
100% Natural Bran Q 120 1.00
All-Bran K 70 0.33
All-Bran with Extra Fiber K 50 0.50
Almond Delight R 110 0.75
Apple Cinnamon Cheerios G 110 0.75
Apple Jacks K 110 1.00
Basic 4 G 130 0.75
Bran Chex R 90 0.67
Bran Flakes P 90 0.67
Cap'n'Crunch Q 120 0.75
Cheerios G 110 1.25
Cinnamon Toast Crunch G 120 0.75
Clusters G 110 0.50
Cocoa Puffs G 110 1.00
Corn Chex R 110 1.00
Corn Flakes K 100 1.00
Corn Pops K 110 1.00
Count Chocula G 110 1.00
Cracklin' Oat Bran K 110 0.50
Cream of Wheat (Quick) N 100 1.00
Crispix K 110 1.00
Crispy Wheat & Raisins G 100 0.75
Double Chex R 100 0.75
Froot Loops K 110 1.00
Frosted Flakes K 110 0.75
Frosted Mini-Wheats K 100 0.80
Fruit & Fibre Dates; Walnuts; and Oats P 120 0.67
Fruitful Bran K 120 0.67
Fruity Pebbles P 110 0.75
Golden Crisp P 100 0.88
Golden Grahams G 110 0.75
Grape Nuts Flakes P 100 0.88
Grape-Nuts P 110 0.25
Great Grains Pecan P 120 0.33
Honey Graham Ohs Q 120 1.00
Honey Nut Cheerios G 110 0.75
Honey-comb P 110 1.33
Just Right Crunchy Nuggets K 110 1.00
Just Right Fruit & Nut K 140 0.75
Kix G 110 1.50
Life Q 100 0.67
Lucky Charms G 110 1.00
Maypo A 100 1.00
Muesli Raisins; Dates; & Almonds R 150 1.00
Muesli Raisins; Peaches; & Pecans R 150 1.00
Mueslix Crispy Blend K 160 0.67
Multi-Grain Cheerios G 100 1.00
Nut&Honey Crunch K 120 0.67
Nutri-Grain Almond-Raisin K 140 0.67
Nutri-grain Wheat K 90 1.00
Oatmeal Raisin Crisp G 130 0.50
Post Nat. Raisin Bran P 120 0.67
Product 19 K 100 1.00
Puffed Rice Q 50 1.00
Puffed Wheat Q 50 1.00
Quaker Oat Squares Q 100 0.50
Quaker Oatmeal Q 100 0.67
Raisin Bran K 120 0.75
Raisin Nut Bran G 100 0.50
Raisin Squares K 90 0.50
Rice Chex R 110 1.13
Rice Krispies K 110 1.00
Shredded Wheat N 80 1.00
Shredded Wheat 'n'Bran N 90 0.67
Shredded Wheat spoon size N 90 0.67
Smacks K 110 0.75
Special K K 110 1.00
Strawberry Fruit Wheats N 90 1.00
Total Corn Flakes G 110 1.00
Total Raisin Bran G 140 1.00
Total Whole Grain G 100 1.00
Triples G 110 0.75
Trix G 110 1.00
Wheat Chex R 100 0.67
Wheaties G 100 1.00
Wheaties Honey Gold G 110 0.75

mutate()

knitr::include_graphics("https://github.com/allisonhorst/stats-illustrations/raw/main/rstats-artwork/dplyr_mutate.png")

A cartoon illustration of a scientist holding a glowing test tube, from which several hexagonal shapes are emerging and transforming as they float upward. The scientist, dressed in a lab coat and safety goggles, symbolizes the concept of mutation, representing the 'mutate()' function from the 'dplyr' package in R. This function is used to modify or create new variables in a dataset, depicted here as hexagonal shapes changing form.

Artwork by Allison Horst

mutate() to include a new variable

cereal |> 
  mutate(potass_per_cup = potass / cups)


name manuf type calories protein fat sodium fiber carbo sugars potass vitamins shelf weight cups rating potass_per_cup
100% Bran N cold 70 4 1 130 10.0 5.0 6 280 25 3 1.00 0.33 68.40297 848.484848
100% Natural Bran Q cold 120 3 5 15 2.0 8.0 8 135 0 3 1.00 1.00 33.98368 135.000000
All-Bran K cold 70 4 1 260 9.0 7.0 5 320 25 3 1.00 0.33 59.42551 969.696970
All-Bran with Extra Fiber K cold 50 4 0 140 14.0 8.0 0 330 25 3 1.00 0.50 93.70491 660.000000
Almond Delight R cold 110 2 2 200 1.0 14.0 8 -1 25 3 1.00 0.75 34.38484 -1.333333
Apple Cinnamon Cheerios G cold 110 2 2 180 1.5 10.5 10 70 25 1 1.00 0.75 29.50954 93.333333
Apple Jacks K cold 110 2 0 125 1.0 11.0 14 30 25 2 1.00 1.00 33.17409 30.000000
Basic 4 G cold 130 3 2 210 2.0 18.0 8 100 25 3 1.33 0.75 37.03856 133.333333
Bran Chex R cold 90 2 1 200 4.0 15.0 6 125 25 1 1.00 0.67 49.12025 186.567164
Bran Flakes P cold 90 3 0 210 5.0 13.0 5 190 25 3 1.00 0.67 53.31381 283.582090
Cap'n'Crunch Q cold 120 1 2 220 0.0 12.0 12 35 25 2 1.00 0.75 18.04285 46.666667
Cheerios G cold 110 6 2 290 2.0 17.0 1 105 25 1 1.00 1.25 50.76500 84.000000
Cinnamon Toast Crunch G cold 120 1 3 210 0.0 13.0 9 45 25 2 1.00 0.75 19.82357 60.000000
Clusters G cold 110 3 2 140 2.0 13.0 7 105 25 3 1.00 0.50 40.40021 210.000000
Cocoa Puffs G cold 110 1 1 180 0.0 12.0 13 55 25 2 1.00 1.00 22.73645 55.000000
Corn Chex R cold 110 2 0 280 0.0 22.0 3 25 25 1 1.00 1.00 41.44502 25.000000
Corn Flakes K cold 100 2 0 290 1.0 21.0 2 35 25 1 1.00 1.00 45.86332 35.000000
Corn Pops K cold 110 1 0 90 1.0 13.0 12 20 25 2 1.00 1.00 35.78279 20.000000
Count Chocula G cold 110 1 1 180 0.0 12.0 13 65 25 2 1.00 1.00 22.39651 65.000000
Cracklin' Oat Bran K cold 110 3 3 140 4.0 10.0 7 160 25 3 1.00 0.50 40.44877 320.000000
Cream of Wheat (Quick) N hot 100 3 0 80 1.0 21.0 0 -1 0 2 1.00 1.00 64.53382 -1.000000
Crispix K cold 110 2 0 220 1.0 21.0 3 30 25 3 1.00 1.00 46.89564 30.000000
Crispy Wheat & Raisins G cold 100 2 1 140 2.0 11.0 10 120 25 3 1.00 0.75 36.17620 160.000000
Double Chex R cold 100 2 0 190 1.0 18.0 5 80 25 3 1.00 0.75 44.33086 106.666667
Froot Loops K cold 110 2 1 125 1.0 11.0 13 30 25 2 1.00 1.00 32.20758 30.000000
Frosted Flakes K cold 110 1 0 200 1.0 14.0 11 25 25 1 1.00 0.75 31.43597 33.333333
Frosted Mini-Wheats K cold 100 3 0 0 3.0 14.0 7 100 25 2 1.00 0.80 58.34514 125.000000
Fruit & Fibre Dates; Walnuts; and Oats P cold 120 3 2 160 5.0 12.0 10 200 25 3 1.25 0.67 40.91705 298.507463
Fruitful Bran K cold 120 3 0 240 5.0 14.0 12 190 25 3 1.33 0.67 41.01549 283.582090
Fruity Pebbles P cold 110 1 1 135 0.0 13.0 12 25 25 2 1.00 0.75 28.02576 33.333333
Golden Crisp P cold 100 2 0 45 0.0 11.0 15 40 25 1 1.00 0.88 35.25244 45.454546
Golden Grahams G cold 110 1 1 280 0.0 15.0 9 45 25 2 1.00 0.75 23.80404 60.000000
Grape Nuts Flakes P cold 100 3 1 140 3.0 15.0 5 85 25 3 1.00 0.88 52.07690 96.590909
Grape-Nuts P cold 110 3 0 170 3.0 17.0 3 90 25 3 1.00 0.25 53.37101 360.000000
Great Grains Pecan P cold 120 3 3 75 3.0 13.0 4 100 25 3 1.00 0.33 45.81172 303.030303
Honey Graham Ohs Q cold 120 1 2 220 1.0 12.0 11 45 25 2 1.00 1.00 21.87129 45.000000
Honey Nut Cheerios G cold 110 3 1 250 1.5 11.5 10 90 25 1 1.00 0.75 31.07222 120.000000
Honey-comb P cold 110 1 0 180 0.0 14.0 11 35 25 1 1.00 1.33 28.74241 26.315790
Just Right Crunchy Nuggets K cold 110 2 1 170 1.0 17.0 6 60 100 3 1.00 1.00 36.52368 60.000000
Just Right Fruit & Nut K cold 140 3 1 170 2.0 20.0 9 95 100 3 1.30 0.75 36.47151 126.666667
Kix G cold 110 2 1 260 0.0 21.0 3 40 25 2 1.00 1.50 39.24111 26.666667
Life Q cold 100 4 2 150 2.0 12.0 6 95 25 2 1.00 0.67 45.32807 141.791045
Lucky Charms G cold 110 2 1 180 0.0 12.0 12 55 25 2 1.00 1.00 26.73451 55.000000
Maypo A hot 100 4 1 0 0.0 16.0 3 95 25 2 1.00 1.00 54.85092 95.000000
Muesli Raisins; Dates; & Almonds R cold 150 4 3 95 3.0 16.0 11 170 25 3 1.00 1.00 37.13686 170.000000
Muesli Raisins; Peaches; & Pecans R cold 150 4 3 150 3.0 16.0 11 170 25 3 1.00 1.00 34.13976 170.000000
Mueslix Crispy Blend K cold 160 3 2 150 3.0 17.0 13 160 25 3 1.50 0.67 30.31335 238.805970
Multi-Grain Cheerios G cold 100 2 1 220 2.0 15.0 6 90 25 1 1.00 1.00 40.10596 90.000000
Nut&Honey Crunch K cold 120 2 1 190 0.0 15.0 9 40 25 2 1.00 0.67 29.92429 59.701493
Nutri-Grain Almond-Raisin K cold 140 3 2 220 3.0 21.0 7 130 25 3 1.33 0.67 40.69232 194.029851
Nutri-grain Wheat K cold 90 3 0 170 3.0 18.0 2 90 25 3 1.00 1.00 59.64284 90.000000
Oatmeal Raisin Crisp G cold 130 3 2 170 1.5 13.5 10 120 25 3 1.25 0.50 30.45084 240.000000
Post Nat. Raisin Bran P cold 120 3 1 200 6.0 11.0 14 260 25 3 1.33 0.67 37.84059 388.059702
Product 19 K cold 100 3 0 320 1.0 20.0 3 45 100 3 1.00 1.00 41.50354 45.000000
Puffed Rice Q cold 50 1 0 0 0.0 13.0 0 15 0 3 0.50 1.00 60.75611 15.000000
Puffed Wheat Q cold 50 2 0 0 1.0 10.0 0 50 0 3 0.50 1.00 63.00565 50.000000
Quaker Oat Squares Q cold 100 4 1 135 2.0 14.0 6 110 25 3 1.00 0.50 49.51187 220.000000
Quaker Oatmeal Q hot 100 5 2 0 2.7 -1.0 -1 110 0 1 1.00 0.67 50.82839 164.179104
Raisin Bran K cold 120 3 1 210 5.0 14.0 12 240 25 2 1.33 0.75 39.25920 320.000000
Raisin Nut Bran G cold 100 3 2 140 2.5 10.5 8 140 25 3 1.00 0.50 39.70340 280.000000
Raisin Squares K cold 90 2 0 0 2.0 15.0 6 110 25 3 1.00 0.50 55.33314 220.000000
Rice Chex R cold 110 1 0 240 0.0 23.0 2 30 25 1 1.00 1.13 41.99893 26.548673
Rice Krispies K cold 110 2 0 290 0.0 22.0 3 35 25 1 1.00 1.00 40.56016 35.000000
Shredded Wheat N cold 80 2 0 0 3.0 16.0 0 95 0 1 0.83 1.00 68.23588 95.000000
Shredded Wheat 'n'Bran N cold 90 3 0 0 4.0 19.0 0 140 0 1 1.00 0.67 74.47295 208.955224
Shredded Wheat spoon size N cold 90 3 0 0 3.0 20.0 0 120 0 1 1.00 0.67 72.80179 179.104478
Smacks K cold 110 2 1 70 1.0 9.0 15 40 25 2 1.00 0.75 31.23005 53.333333
Special K K cold 110 6 0 230 1.0 16.0 3 55 25 1 1.00 1.00 53.13132 55.000000
Strawberry Fruit Wheats N cold 90 2 0 15 3.0 15.0 5 90 25 2 1.00 1.00 59.36399 90.000000
Total Corn Flakes G cold 110 2 1 200 0.0 21.0 3 35 100 3 1.00 1.00 38.83975 35.000000
Total Raisin Bran G cold 140 3 1 190 4.0 15.0 14 230 100 3 1.50 1.00 28.59278 230.000000
Total Whole Grain G cold 100 3 1 200 3.0 16.0 3 110 100 3 1.00 1.00 46.65884 110.000000
Triples G cold 110 2 1 250 0.0 21.0 3 60 25 3 1.00 0.75 39.10617 80.000000
Trix G cold 110 1 1 140 0.0 13.0 12 25 25 2 1.00 1.00 27.75330 25.000000
Wheat Chex R cold 100 3 1 230 3.0 17.0 3 115 25 1 1.00 0.67 49.78744 171.641791
Wheaties G cold 100 3 1 200 3.0 17.0 3 110 25 1 1.00 1.00 51.59219 110.000000
Wheaties Honey Gold G cold 110 2 1 200 1.0 16.0 8 60 25 1 1.00 0.75 36.18756 80.000000

mutate() to change an existing variable

cereal |> 
  mutate(shelf = as.factor(shelf))


name manuf type calories protein fat sodium fiber carbo sugars potass vitamins shelf weight cups rating
100% Bran N cold 70 4 1 130 10.0 5.0 6 280 25 3 1.00 0.33 68.40297
100% Natural Bran Q cold 120 3 5 15 2.0 8.0 8 135 0 3 1.00 1.00 33.98368
All-Bran K cold 70 4 1 260 9.0 7.0 5 320 25 3 1.00 0.33 59.42551
All-Bran with Extra Fiber K cold 50 4 0 140 14.0 8.0 0 330 25 3 1.00 0.50 93.70491
Almond Delight R cold 110 2 2 200 1.0 14.0 8 -1 25 3 1.00 0.75 34.38484
Apple Cinnamon Cheerios G cold 110 2 2 180 1.5 10.5 10 70 25 1 1.00 0.75 29.50954
Apple Jacks K cold 110 2 0 125 1.0 11.0 14 30 25 2 1.00 1.00 33.17409
Basic 4 G cold 130 3 2 210 2.0 18.0 8 100 25 3 1.33 0.75 37.03856
Bran Chex R cold 90 2 1 200 4.0 15.0 6 125 25 1 1.00 0.67 49.12025
Bran Flakes P cold 90 3 0 210 5.0 13.0 5 190 25 3 1.00 0.67 53.31381
Cap'n'Crunch Q cold 120 1 2 220 0.0 12.0 12 35 25 2 1.00 0.75 18.04285
Cheerios G cold 110 6 2 290 2.0 17.0 1 105 25 1 1.00 1.25 50.76500
Cinnamon Toast Crunch G cold 120 1 3 210 0.0 13.0 9 45 25 2 1.00 0.75 19.82357
Clusters G cold 110 3 2 140 2.0 13.0 7 105 25 3 1.00 0.50 40.40021
Cocoa Puffs G cold 110 1 1 180 0.0 12.0 13 55 25 2 1.00 1.00 22.73645
Corn Chex R cold 110 2 0 280 0.0 22.0 3 25 25 1 1.00 1.00 41.44502
Corn Flakes K cold 100 2 0 290 1.0 21.0 2 35 25 1 1.00 1.00 45.86332
Corn Pops K cold 110 1 0 90 1.0 13.0 12 20 25 2 1.00 1.00 35.78279
Count Chocula G cold 110 1 1 180 0.0 12.0 13 65 25 2 1.00 1.00 22.39651
Cracklin' Oat Bran K cold 110 3 3 140 4.0 10.0 7 160 25 3 1.00 0.50 40.44877
Cream of Wheat (Quick) N hot 100 3 0 80 1.0 21.0 0 -1 0 2 1.00 1.00 64.53382
Crispix K cold 110 2 0 220 1.0 21.0 3 30 25 3 1.00 1.00 46.89564
Crispy Wheat & Raisins G cold 100 2 1 140 2.0 11.0 10 120 25 3 1.00 0.75 36.17620
Double Chex R cold 100 2 0 190 1.0 18.0 5 80 25 3 1.00 0.75 44.33086
Froot Loops K cold 110 2 1 125 1.0 11.0 13 30 25 2 1.00 1.00 32.20758
Frosted Flakes K cold 110 1 0 200 1.0 14.0 11 25 25 1 1.00 0.75 31.43597
Frosted Mini-Wheats K cold 100 3 0 0 3.0 14.0 7 100 25 2 1.00 0.80 58.34514
Fruit & Fibre Dates; Walnuts; and Oats P cold 120 3 2 160 5.0 12.0 10 200 25 3 1.25 0.67 40.91705
Fruitful Bran K cold 120 3 0 240 5.0 14.0 12 190 25 3 1.33 0.67 41.01549
Fruity Pebbles P cold 110 1 1 135 0.0 13.0 12 25 25 2 1.00 0.75 28.02576
Golden Crisp P cold 100 2 0 45 0.0 11.0 15 40 25 1 1.00 0.88 35.25244
Golden Grahams G cold 110 1 1 280 0.0 15.0 9 45 25 2 1.00 0.75 23.80404
Grape Nuts Flakes P cold 100 3 1 140 3.0 15.0 5 85 25 3 1.00 0.88 52.07690
Grape-Nuts P cold 110 3 0 170 3.0 17.0 3 90 25 3 1.00 0.25 53.37101
Great Grains Pecan P cold 120 3 3 75 3.0 13.0 4 100 25 3 1.00 0.33 45.81172
Honey Graham Ohs Q cold 120 1 2 220 1.0 12.0 11 45 25 2 1.00 1.00 21.87129
Honey Nut Cheerios G cold 110 3 1 250 1.5 11.5 10 90 25 1 1.00 0.75 31.07222
Honey-comb P cold 110 1 0 180 0.0 14.0 11 35 25 1 1.00 1.33 28.74241
Just Right Crunchy Nuggets K cold 110 2 1 170 1.0 17.0 6 60 100 3 1.00 1.00 36.52368
Just Right Fruit & Nut K cold 140 3 1 170 2.0 20.0 9 95 100 3 1.30 0.75 36.47151
Kix G cold 110 2 1 260 0.0 21.0 3 40 25 2 1.00 1.50 39.24111
Life Q cold 100 4 2 150 2.0 12.0 6 95 25 2 1.00 0.67 45.32807
Lucky Charms G cold 110 2 1 180 0.0 12.0 12 55 25 2 1.00 1.00 26.73451
Maypo A hot 100 4 1 0 0.0 16.0 3 95 25 2 1.00 1.00 54.85092
Muesli Raisins; Dates; & Almonds R cold 150 4 3 95 3.0 16.0 11 170 25 3 1.00 1.00 37.13686
Muesli Raisins; Peaches; & Pecans R cold 150 4 3 150 3.0 16.0 11 170 25 3 1.00 1.00 34.13976
Mueslix Crispy Blend K cold 160 3 2 150 3.0 17.0 13 160 25 3 1.50 0.67 30.31335
Multi-Grain Cheerios G cold 100 2 1 220 2.0 15.0 6 90 25 1 1.00 1.00 40.10596
Nut&Honey Crunch K cold 120 2 1 190 0.0 15.0 9 40 25 2 1.00 0.67 29.92429
Nutri-Grain Almond-Raisin K cold 140 3 2 220 3.0 21.0 7 130 25 3 1.33 0.67 40.69232
Nutri-grain Wheat K cold 90 3 0 170 3.0 18.0 2 90 25 3 1.00 1.00 59.64284
Oatmeal Raisin Crisp G cold 130 3 2 170 1.5 13.5 10 120 25 3 1.25 0.50 30.45084
Post Nat. Raisin Bran P cold 120 3 1 200 6.0 11.0 14 260 25 3 1.33 0.67 37.84059
Product 19 K cold 100 3 0 320 1.0 20.0 3 45 100 3 1.00 1.00 41.50354
Puffed Rice Q cold 50 1 0 0 0.0 13.0 0 15 0 3 0.50 1.00 60.75611
Puffed Wheat Q cold 50 2 0 0 1.0 10.0 0 50 0 3 0.50 1.00 63.00565
Quaker Oat Squares Q cold 100 4 1 135 2.0 14.0 6 110 25 3 1.00 0.50 49.51187
Quaker Oatmeal Q hot 100 5 2 0 2.7 -1.0 -1 110 0 1 1.00 0.67 50.82839
Raisin Bran K cold 120 3 1 210 5.0 14.0 12 240 25 2 1.33 0.75 39.25920
Raisin Nut Bran G cold 100 3 2 140 2.5 10.5 8 140 25 3 1.00 0.50 39.70340
Raisin Squares K cold 90 2 0 0 2.0 15.0 6 110 25 3 1.00 0.50 55.33314
Rice Chex R cold 110 1 0 240 0.0 23.0 2 30 25 1 1.00 1.13 41.99893
Rice Krispies K cold 110 2 0 290 0.0 22.0 3 35 25 1 1.00 1.00 40.56016
Shredded Wheat N cold 80 2 0 0 3.0 16.0 0 95 0 1 0.83 1.00 68.23588
Shredded Wheat 'n'Bran N cold 90 3 0 0 4.0 19.0 0 140 0 1 1.00 0.67 74.47295
Shredded Wheat spoon size N cold 90 3 0 0 3.0 20.0 0 120 0 1 1.00 0.67 72.80179
Smacks K cold 110 2 1 70 1.0 9.0 15 40 25 2 1.00 0.75 31.23005
Special K K cold 110 6 0 230 1.0 16.0 3 55 25 1 1.00 1.00 53.13132
Strawberry Fruit Wheats N cold 90 2 0 15 3.0 15.0 5 90 25 2 1.00 1.00 59.36399
Total Corn Flakes G cold 110 2 1 200 0.0 21.0 3 35 100 3 1.00 1.00 38.83975
Total Raisin Bran G cold 140 3 1 190 4.0 15.0 14 230 100 3 1.50 1.00 28.59278
Total Whole Grain G cold 100 3 1 200 3.0 16.0 3 110 100 3 1.00 1.00 46.65884
Triples G cold 110 2 1 250 0.0 21.0 3 60 25 3 1.00 0.75 39.10617
Trix G cold 110 1 1 140 0.0 13.0 12 25 25 2 1.00 1.00 27.75330
Wheat Chex R cold 100 3 1 230 3.0 17.0 3 115 25 1 1.00 0.67 49.78744
Wheaties G cold 100 3 1 200 3.0 17.0 3 110 25 1 1.00 1.00 51.59219
Wheaties Honey Gold G cold 110 2 1 200 1.0 16.0 8 60 25 1 1.00 0.75 36.18756

mutate(): Handy Helpers!

  • if_else(): creating a new variable with two levels
  • case_when(): creating a new variable with three or more levels
    • Pssst, don’t use nested if_else() functions.
  • as.factor(), as.numeric(), etc. : change variable type
  • +, -, *, / : basic mathematical operations
  • %% : modulo (returns the remainder when doing division)

How do we “mutate” in base R?

You can define new columns…

cereal$potass_per_cup <- cereal$potass / cereal$cups
name manuf type calories protein fat sodium fiber carbo sugars potass vitamins shelf weight cups rating potass_per_cup
100% Bran N cold 70 4 1 130 10.0 5.0 6 280 25 3 1.00 0.33 68.40297 848.484848
100% Natural Bran Q cold 120 3 5 15 2.0 8.0 8 135 0 3 1.00 1.00 33.98368 135.000000
All-Bran K cold 70 4 1 260 9.0 7.0 5 320 25 3 1.00 0.33 59.42551 969.696970
All-Bran with Extra Fiber K cold 50 4 0 140 14.0 8.0 0 330 25 3 1.00 0.50 93.70491 660.000000
Almond Delight R cold 110 2 2 200 1.0 14.0 8 -1 25 3 1.00 0.75 34.38484 -1.333333
Apple Cinnamon Cheerios G cold 110 2 2 180 1.5 10.5 10 70 25 1 1.00 0.75 29.50954 93.333333
Apple Jacks K cold 110 2 0 125 1.0 11.0 14 30 25 2 1.00 1.00 33.17409 30.000000
Basic 4 G cold 130 3 2 210 2.0 18.0 8 100 25 3 1.33 0.75 37.03856 133.333333
Bran Chex R cold 90 2 1 200 4.0 15.0 6 125 25 1 1.00 0.67 49.12025 186.567164
Bran Flakes P cold 90 3 0 210 5.0 13.0 5 190 25 3 1.00 0.67 53.31381 283.582090
Cap'n'Crunch Q cold 120 1 2 220 0.0 12.0 12 35 25 2 1.00 0.75 18.04285 46.666667
Cheerios G cold 110 6 2 290 2.0 17.0 1 105 25 1 1.00 1.25 50.76500 84.000000
Cinnamon Toast Crunch G cold 120 1 3 210 0.0 13.0 9 45 25 2 1.00 0.75 19.82357 60.000000
Clusters G cold 110 3 2 140 2.0 13.0 7 105 25 3 1.00 0.50 40.40021 210.000000
Cocoa Puffs G cold 110 1 1 180 0.0 12.0 13 55 25 2 1.00 1.00 22.73645 55.000000
Corn Chex R cold 110 2 0 280 0.0 22.0 3 25 25 1 1.00 1.00 41.44502 25.000000
Corn Flakes K cold 100 2 0 290 1.0 21.0 2 35 25 1 1.00 1.00 45.86332 35.000000
Corn Pops K cold 110 1 0 90 1.0 13.0 12 20 25 2 1.00 1.00 35.78279 20.000000
Count Chocula G cold 110 1 1 180 0.0 12.0 13 65 25 2 1.00 1.00 22.39651 65.000000
Cracklin' Oat Bran K cold 110 3 3 140 4.0 10.0 7 160 25 3 1.00 0.50 40.44877 320.000000
Cream of Wheat (Quick) N hot 100 3 0 80 1.0 21.0 0 -1 0 2 1.00 1.00 64.53382 -1.000000
Crispix K cold 110 2 0 220 1.0 21.0 3 30 25 3 1.00 1.00 46.89564 30.000000
Crispy Wheat & Raisins G cold 100 2 1 140 2.0 11.0 10 120 25 3 1.00 0.75 36.17620 160.000000
Double Chex R cold 100 2 0 190 1.0 18.0 5 80 25 3 1.00 0.75 44.33086 106.666667
Froot Loops K cold 110 2 1 125 1.0 11.0 13 30 25 2 1.00 1.00 32.20758 30.000000
Frosted Flakes K cold 110 1 0 200 1.0 14.0 11 25 25 1 1.00 0.75 31.43597 33.333333
Frosted Mini-Wheats K cold 100 3 0 0 3.0 14.0 7 100 25 2 1.00 0.80 58.34514 125.000000
Fruit & Fibre Dates; Walnuts; and Oats P cold 120 3 2 160 5.0 12.0 10 200 25 3 1.25 0.67 40.91705 298.507463
Fruitful Bran K cold 120 3 0 240 5.0 14.0 12 190 25 3 1.33 0.67 41.01549 283.582090
Fruity Pebbles P cold 110 1 1 135 0.0 13.0 12 25 25 2 1.00 0.75 28.02576 33.333333
Golden Crisp P cold 100 2 0 45 0.0 11.0 15 40 25 1 1.00 0.88 35.25244 45.454546
Golden Grahams G cold 110 1 1 280 0.0 15.0 9 45 25 2 1.00 0.75 23.80404 60.000000
Grape Nuts Flakes P cold 100 3 1 140 3.0 15.0 5 85 25 3 1.00 0.88 52.07690 96.590909
Grape-Nuts P cold 110 3 0 170 3.0 17.0 3 90 25 3 1.00 0.25 53.37101 360.000000
Great Grains Pecan P cold 120 3 3 75 3.0 13.0 4 100 25 3 1.00 0.33 45.81172 303.030303
Honey Graham Ohs Q cold 120 1 2 220 1.0 12.0 11 45 25 2 1.00 1.00 21.87129 45.000000
Honey Nut Cheerios G cold 110 3 1 250 1.5 11.5 10 90 25 1 1.00 0.75 31.07222 120.000000
Honey-comb P cold 110 1 0 180 0.0 14.0 11 35 25 1 1.00 1.33 28.74241 26.315790
Just Right Crunchy Nuggets K cold 110 2 1 170 1.0 17.0 6 60 100 3 1.00 1.00 36.52368 60.000000
Just Right Fruit & Nut K cold 140 3 1 170 2.0 20.0 9 95 100 3 1.30 0.75 36.47151 126.666667
Kix G cold 110 2 1 260 0.0 21.0 3 40 25 2 1.00 1.50 39.24111 26.666667
Life Q cold 100 4 2 150 2.0 12.0 6 95 25 2 1.00 0.67 45.32807 141.791045
Lucky Charms G cold 110 2 1 180 0.0 12.0 12 55 25 2 1.00 1.00 26.73451 55.000000
Maypo A hot 100 4 1 0 0.0 16.0 3 95 25 2 1.00 1.00 54.85092 95.000000
Muesli Raisins; Dates; & Almonds R cold 150 4 3 95 3.0 16.0 11 170 25 3 1.00 1.00 37.13686 170.000000
Muesli Raisins; Peaches; & Pecans R cold 150 4 3 150 3.0 16.0 11 170 25 3 1.00 1.00 34.13976 170.000000
Mueslix Crispy Blend K cold 160 3 2 150 3.0 17.0 13 160 25 3 1.50 0.67 30.31335 238.805970
Multi-Grain Cheerios G cold 100 2 1 220 2.0 15.0 6 90 25 1 1.00 1.00 40.10596 90.000000
Nut&Honey Crunch K cold 120 2 1 190 0.0 15.0 9 40 25 2 1.00 0.67 29.92429 59.701493
Nutri-Grain Almond-Raisin K cold 140 3 2 220 3.0 21.0 7 130 25 3 1.33 0.67 40.69232 194.029851
Nutri-grain Wheat K cold 90 3 0 170 3.0 18.0 2 90 25 3 1.00 1.00 59.64284 90.000000
Oatmeal Raisin Crisp G cold 130 3 2 170 1.5 13.5 10 120 25 3 1.25 0.50 30.45084 240.000000
Post Nat. Raisin Bran P cold 120 3 1 200 6.0 11.0 14 260 25 3 1.33 0.67 37.84059 388.059702
Product 19 K cold 100 3 0 320 1.0 20.0 3 45 100 3 1.00 1.00 41.50354 45.000000
Puffed Rice Q cold 50 1 0 0 0.0 13.0 0 15 0 3 0.50 1.00 60.75611 15.000000
Puffed Wheat Q cold 50 2 0 0 1.0 10.0 0 50 0 3 0.50 1.00 63.00565 50.000000
Quaker Oat Squares Q cold 100 4 1 135 2.0 14.0 6 110 25 3 1.00 0.50 49.51187 220.000000
Quaker Oatmeal Q hot 100 5 2 0 2.7 -1.0 -1 110 0 1 1.00 0.67 50.82839 164.179104
Raisin Bran K cold 120 3 1 210 5.0 14.0 12 240 25 2 1.33 0.75 39.25920 320.000000
Raisin Nut Bran G cold 100 3 2 140 2.5 10.5 8 140 25 3 1.00 0.50 39.70340 280.000000
Raisin Squares K cold 90 2 0 0 2.0 15.0 6 110 25 3 1.00 0.50 55.33314 220.000000
Rice Chex R cold 110 1 0 240 0.0 23.0 2 30 25 1 1.00 1.13 41.99893 26.548673
Rice Krispies K cold 110 2 0 290 0.0 22.0 3 35 25 1 1.00 1.00 40.56016 35.000000
Shredded Wheat N cold 80 2 0 0 3.0 16.0 0 95 0 1 0.83 1.00 68.23588 95.000000
Shredded Wheat 'n'Bran N cold 90 3 0 0 4.0 19.0 0 140 0 1 1.00 0.67 74.47295 208.955224
Shredded Wheat spoon size N cold 90 3 0 0 3.0 20.0 0 120 0 1 1.00 0.67 72.80179 179.104478
Smacks K cold 110 2 1 70 1.0 9.0 15 40 25 2 1.00 0.75 31.23005 53.333333
Special K K cold 110 6 0 230 1.0 16.0 3 55 25 1 1.00 1.00 53.13132 55.000000
Strawberry Fruit Wheats N cold 90 2 0 15 3.0 15.0 5 90 25 2 1.00 1.00 59.36399 90.000000
Total Corn Flakes G cold 110 2 1 200 0.0 21.0 3 35 100 3 1.00 1.00 38.83975 35.000000
Total Raisin Bran G cold 140 3 1 190 4.0 15.0 14 230 100 3 1.50 1.00 28.59278 230.000000
Total Whole Grain G cold 100 3 1 200 3.0 16.0 3 110 100 3 1.00 1.00 46.65884 110.000000
Triples G cold 110 2 1 250 0.0 21.0 3 60 25 3 1.00 0.75 39.10617 80.000000
Trix G cold 110 1 1 140 0.0 13.0 12 25 25 2 1.00 1.00 27.75330 25.000000
Wheat Chex R cold 100 3 1 230 3.0 17.0 3 115 25 1 1.00 0.67 49.78744 171.641791
Wheaties G cold 100 3 1 200 3.0 17.0 3 110 25 1 1.00 1.00 51.59219 110.000000
Wheaties Honey Gold G cold 110 2 1 200 1.0 16.0 8 60 25 1 1.00 0.75 36.18756 80.000000

. . .


…OR overwrite old ones!

cereal$shelf <- as.factor(cereal$shelf)

group_by()

knitr::include_graphics("https://raw.githubusercontent.com/allisonhorst/stats-illustrations/main/rstats-blanks/ungroup_blank.png")

A cartoon illustration of a group of animals, including a horse, a cow, a sheep, and a chicken, standing closely together inside a lasso. The lasso represents grouping, and the animals appear calm and organized. Outside the lasso, there is an open space, suggesting the concept of 'ungrouping' in data manipulation, where the grouping is removed and entities are no longer confined to the same category or structure. This represents the 'ungroup()' function in R's dplyr package, symbolizing the removal of grouping from data.

Artwork by Allison Horst

group_by()

Separate the data into different groups based on a categorical variable.

. . .

The data gets grouped, but nothing happens externally.

cereal |> 
  group_by(type)
# A tibble: 77 × 16
# Groups:   type [2]
   name      manuf type  calories protein   fat sodium fiber carbo sugars potass
   <fct>     <fct> <fct>    <int>   <int> <int>  <int> <dbl> <dbl>  <int>  <int>
 1 100% Bran N     cold        70       4     1    130  10     5        6    280
 2 100% Nat… Q     cold       120       3     5     15   2     8        8    135
 3 All-Bran  K     cold        70       4     1    260   9     7        5    320
 4 All-Bran… K     cold        50       4     0    140  14     8        0    330
 5 Almond D… R     cold       110       2     2    200   1    14        8     -1
 6 Apple Ci… G     cold       110       2     2    180   1.5  10.5     10     70
 7 Apple Ja… K     cold       110       2     0    125   1    11       14     30
 8 Basic 4   G     cold       130       3     2    210   2    18        8    100
 9 Bran Chex R     cold        90       2     1    200   4    15        6    125
10 Bran Fla… P     cold        90       3     0    210   5    13        5    190
# ℹ 67 more rows
# ℹ 5 more variables: vitamins <int>, shelf <int>, weight <dbl>, cups <dbl>,
#   rating <dbl>
name manuf type calories protein fat sodium fiber carbo sugars potass vitamins shelf weight cups rating
100% Bran N cold 70 4 1 130 10.0 5.0 6 280 25 3 1.00 0.33 68.40297
100% Natural Bran Q cold 120 3 5 15 2.0 8.0 8 135 0 3 1.00 1.00 33.98368
All-Bran K cold 70 4 1 260 9.0 7.0 5 320 25 3 1.00 0.33 59.42551
All-Bran with Extra Fiber K cold 50 4 0 140 14.0 8.0 0 330 25 3 1.00 0.50 93.70491
Almond Delight R cold 110 2 2 200 1.0 14.0 8 -1 25 3 1.00 0.75 34.38484
Apple Cinnamon Cheerios G cold 110 2 2 180 1.5 10.5 10 70 25 1 1.00 0.75 29.50954
Apple Jacks K cold 110 2 0 125 1.0 11.0 14 30 25 2 1.00 1.00 33.17409
Basic 4 G cold 130 3 2 210 2.0 18.0 8 100 25 3 1.33 0.75 37.03856
Bran Chex R cold 90 2 1 200 4.0 15.0 6 125 25 1 1.00 0.67 49.12025
Bran Flakes P cold 90 3 0 210 5.0 13.0 5 190 25 3 1.00 0.67 53.31381
Cap'n'Crunch Q cold 120 1 2 220 0.0 12.0 12 35 25 2 1.00 0.75 18.04285
Cheerios G cold 110 6 2 290 2.0 17.0 1 105 25 1 1.00 1.25 50.76500
Cinnamon Toast Crunch G cold 120 1 3 210 0.0 13.0 9 45 25 2 1.00 0.75 19.82357
Clusters G cold 110 3 2 140 2.0 13.0 7 105 25 3 1.00 0.50 40.40021
Cocoa Puffs G cold 110 1 1 180 0.0 12.0 13 55 25 2 1.00 1.00 22.73645
Corn Chex R cold 110 2 0 280 0.0 22.0 3 25 25 1 1.00 1.00 41.44502
Corn Flakes K cold 100 2 0 290 1.0 21.0 2 35 25 1 1.00 1.00 45.86332
Corn Pops K cold 110 1 0 90 1.0 13.0 12 20 25 2 1.00 1.00 35.78279
Count Chocula G cold 110 1 1 180 0.0 12.0 13 65 25 2 1.00 1.00 22.39651
Cracklin' Oat Bran K cold 110 3 3 140 4.0 10.0 7 160 25 3 1.00 0.50 40.44877
Cream of Wheat (Quick) N hot 100 3 0 80 1.0 21.0 0 -1 0 2 1.00 1.00 64.53382
Crispix K cold 110 2 0 220 1.0 21.0 3 30 25 3 1.00 1.00 46.89564
Crispy Wheat & Raisins G cold 100 2 1 140 2.0 11.0 10 120 25 3 1.00 0.75 36.17620
Double Chex R cold 100 2 0 190 1.0 18.0 5 80 25 3 1.00 0.75 44.33086
Froot Loops K cold 110 2 1 125 1.0 11.0 13 30 25 2 1.00 1.00 32.20758
Frosted Flakes K cold 110 1 0 200 1.0 14.0 11 25 25 1 1.00 0.75 31.43597
Frosted Mini-Wheats K cold 100 3 0 0 3.0 14.0 7 100 25 2 1.00 0.80 58.34514
Fruit & Fibre Dates; Walnuts; and Oats P cold 120 3 2 160 5.0 12.0 10 200 25 3 1.25 0.67 40.91705
Fruitful Bran K cold 120 3 0 240 5.0 14.0 12 190 25 3 1.33 0.67 41.01549
Fruity Pebbles P cold 110 1 1 135 0.0 13.0 12 25 25 2 1.00 0.75 28.02576
Golden Crisp P cold 100 2 0 45 0.0 11.0 15 40 25 1 1.00 0.88 35.25244
Golden Grahams G cold 110 1 1 280 0.0 15.0 9 45 25 2 1.00 0.75 23.80404
Grape Nuts Flakes P cold 100 3 1 140 3.0 15.0 5 85 25 3 1.00 0.88 52.07690
Grape-Nuts P cold 110 3 0 170 3.0 17.0 3 90 25 3 1.00 0.25 53.37101
Great Grains Pecan P cold 120 3 3 75 3.0 13.0 4 100 25 3 1.00 0.33 45.81172
Honey Graham Ohs Q cold 120 1 2 220 1.0 12.0 11 45 25 2 1.00 1.00 21.87129
Honey Nut Cheerios G cold 110 3 1 250 1.5 11.5 10 90 25 1 1.00 0.75 31.07222
Honey-comb P cold 110 1 0 180 0.0 14.0 11 35 25 1 1.00 1.33 28.74241
Just Right Crunchy Nuggets K cold 110 2 1 170 1.0 17.0 6 60 100 3 1.00 1.00 36.52368
Just Right Fruit & Nut K cold 140 3 1 170 2.0 20.0 9 95 100 3 1.30 0.75 36.47151
Kix G cold 110 2 1 260 0.0 21.0 3 40 25 2 1.00 1.50 39.24111
Life Q cold 100 4 2 150 2.0 12.0 6 95 25 2 1.00 0.67 45.32807
Lucky Charms G cold 110 2 1 180 0.0 12.0 12 55 25 2 1.00 1.00 26.73451
Maypo A hot 100 4 1 0 0.0 16.0 3 95 25 2 1.00 1.00 54.85092
Muesli Raisins; Dates; & Almonds R cold 150 4 3 95 3.0 16.0 11 170 25 3 1.00 1.00 37.13686
Muesli Raisins; Peaches; & Pecans R cold 150 4 3 150 3.0 16.0 11 170 25 3 1.00 1.00 34.13976
Mueslix Crispy Blend K cold 160 3 2 150 3.0 17.0 13 160 25 3 1.50 0.67 30.31335
Multi-Grain Cheerios G cold 100 2 1 220 2.0 15.0 6 90 25 1 1.00 1.00 40.10596
Nut&Honey Crunch K cold 120 2 1 190 0.0 15.0 9 40 25 2 1.00 0.67 29.92429
Nutri-Grain Almond-Raisin K cold 140 3 2 220 3.0 21.0 7 130 25 3 1.33 0.67 40.69232
Nutri-grain Wheat K cold 90 3 0 170 3.0 18.0 2 90 25 3 1.00 1.00 59.64284
Oatmeal Raisin Crisp G cold 130 3 2 170 1.5 13.5 10 120 25 3 1.25 0.50 30.45084
Post Nat. Raisin Bran P cold 120 3 1 200 6.0 11.0 14 260 25 3 1.33 0.67 37.84059
Product 19 K cold 100 3 0 320 1.0 20.0 3 45 100 3 1.00 1.00 41.50354
Puffed Rice Q cold 50 1 0 0 0.0 13.0 0 15 0 3 0.50 1.00 60.75611
Puffed Wheat Q cold 50 2 0 0 1.0 10.0 0 50 0 3 0.50 1.00 63.00565
Quaker Oat Squares Q cold 100 4 1 135 2.0 14.0 6 110 25 3 1.00 0.50 49.51187
Quaker Oatmeal Q hot 100 5 2 0 2.7 -1.0 -1 110 0 1 1.00 0.67 50.82839
Raisin Bran K cold 120 3 1 210 5.0 14.0 12 240 25 2 1.33 0.75 39.25920
Raisin Nut Bran G cold 100 3 2 140 2.5 10.5 8 140 25 3 1.00 0.50 39.70340
Raisin Squares K cold 90 2 0 0 2.0 15.0 6 110 25 3 1.00 0.50 55.33314
Rice Chex R cold 110 1 0 240 0.0 23.0 2 30 25 1 1.00 1.13 41.99893
Rice Krispies K cold 110 2 0 290 0.0 22.0 3 35 25 1 1.00 1.00 40.56016
Shredded Wheat N cold 80 2 0 0 3.0 16.0 0 95 0 1 0.83 1.00 68.23588
Shredded Wheat 'n'Bran N cold 90 3 0 0 4.0 19.0 0 140 0 1 1.00 0.67 74.47295
Shredded Wheat spoon size N cold 90 3 0 0 3.0 20.0 0 120 0 1 1.00 0.67 72.80179
Smacks K cold 110 2 1 70 1.0 9.0 15 40 25 2 1.00 0.75 31.23005
Special K K cold 110 6 0 230 1.0 16.0 3 55 25 1 1.00 1.00 53.13132
Strawberry Fruit Wheats N cold 90 2 0 15 3.0 15.0 5 90 25 2 1.00 1.00 59.36399
Total Corn Flakes G cold 110 2 1 200 0.0 21.0 3 35 100 3 1.00 1.00 38.83975
Total Raisin Bran G cold 140 3 1 190 4.0 15.0 14 230 100 3 1.50 1.00 28.59278
Total Whole Grain G cold 100 3 1 200 3.0 16.0 3 110 100 3 1.00 1.00 46.65884
Triples G cold 110 2 1 250 0.0 21.0 3 60 25 3 1.00 0.75 39.10617
Trix G cold 110 1 1 140 0.0 13.0 12 25 25 2 1.00 1.00 27.75330
Wheat Chex R cold 100 3 1 230 3.0 17.0 3 115 25 1 1.00 0.67 49.78744
Wheaties G cold 100 3 1 200 3.0 17.0 3 110 25 1 1.00 1.00 51.59219
Wheaties Honey Gold G cold 110 2 1 200 1.0 16.0 8 60 25 1 1.00 0.75 36.18756

ungroup()

The ungroup() function will remove the internal grouping in your data.

  • This is not something that you always need to do, but if you are getting unexpected output downstream from a group_by() statement, try ungrouping your data!

summarize()

group_by() is almost always paired with summarize()!

summarize()

We can calculate summaries of variables in the data.

. . .

cereal |> 
  summarise(mean_fiber = mean(fiber))
  mean_fiber
1   2.151948

. . .

Or multiple summaries at the same time.

cereal |> 
summarize(mean_fiber = mean(fiber),
          num_cereals = n(),
          mean_sugar = mean(sugars))
  mean_fiber num_cereals mean_sugar
1   2.151948          77   6.922078

summarize(): Handy Helpers!

  • mean(), median(), sd(), sum()
  • min(), max()
  • n(), n_distinct() : counts the number of (distinct) elements
  • first(), last(), nth() : extract the first, last, or nth element

group_by() + summarize()!

  1. group_by a variable (or multiple variables)
  2. summarize a variable (or multiple variables) within the groups
cereal |> 
  group_by(manuf) |> 
  summarise(mean_sugar = mean(sugars))
manuf mean_sugar
A 3.000000
G 7.954546
K 7.565217
N 1.833333
P 8.777778
Q 5.250000
R 6.125000

group_by() + mutate()!

  1. group_by a variable (or multiple variables)
  2. mutate a variable (or multiple variables) within the groups
cereal |> 
  group_by(manuf) |> 
  mutate(mean_sugar = mean(sugars))
name manuf type calories protein fat sodium fiber carbo sugars potass vitamins shelf weight cups rating mean_sugar
100% Bran N cold 70 4 1 130 10.0 5.0 6 280 25 3 1.00 0.33 68.40297 1.833333
100% Natural Bran Q cold 120 3 5 15 2.0 8.0 8 135 0 3 1.00 1.00 33.98368 5.250000
All-Bran K cold 70 4 1 260 9.0 7.0 5 320 25 3 1.00 0.33 59.42551 7.565217
All-Bran with Extra Fiber K cold 50 4 0 140 14.0 8.0 0 330 25 3 1.00 0.50 93.70491 7.565217
Almond Delight R cold 110 2 2 200 1.0 14.0 8 -1 25 3 1.00 0.75 34.38484 6.125000
Apple Cinnamon Cheerios G cold 110 2 2 180 1.5 10.5 10 70 25 1 1.00 0.75 29.50954 7.954546
Apple Jacks K cold 110 2 0 125 1.0 11.0 14 30 25 2 1.00 1.00 33.17409 7.565217
Basic 4 G cold 130 3 2 210 2.0 18.0 8 100 25 3 1.33 0.75 37.03856 7.954546
Bran Chex R cold 90 2 1 200 4.0 15.0 6 125 25 1 1.00 0.67 49.12025 6.125000
Bran Flakes P cold 90 3 0 210 5.0 13.0 5 190 25 3 1.00 0.67 53.31381 8.777778
Cap'n'Crunch Q cold 120 1 2 220 0.0 12.0 12 35 25 2 1.00 0.75 18.04285 5.250000
Cheerios G cold 110 6 2 290 2.0 17.0 1 105 25 1 1.00 1.25 50.76500 7.954546
Cinnamon Toast Crunch G cold 120 1 3 210 0.0 13.0 9 45 25 2 1.00 0.75 19.82357 7.954546
Clusters G cold 110 3 2 140 2.0 13.0 7 105 25 3 1.00 0.50 40.40021 7.954546
Cocoa Puffs G cold 110 1 1 180 0.0 12.0 13 55 25 2 1.00 1.00 22.73645 7.954546
Corn Chex R cold 110 2 0 280 0.0 22.0 3 25 25 1 1.00 1.00 41.44502 6.125000
Corn Flakes K cold 100 2 0 290 1.0 21.0 2 35 25 1 1.00 1.00 45.86332 7.565217
Corn Pops K cold 110 1 0 90 1.0 13.0 12 20 25 2 1.00 1.00 35.78279 7.565217
Count Chocula G cold 110 1 1 180 0.0 12.0 13 65 25 2 1.00 1.00 22.39651 7.954546
Cracklin' Oat Bran K cold 110 3 3 140 4.0 10.0 7 160 25 3 1.00 0.50 40.44877 7.565217
Cream of Wheat (Quick) N hot 100 3 0 80 1.0 21.0 0 -1 0 2 1.00 1.00 64.53382 1.833333
Crispix K cold 110 2 0 220 1.0 21.0 3 30 25 3 1.00 1.00 46.89564 7.565217
Crispy Wheat & Raisins G cold 100 2 1 140 2.0 11.0 10 120 25 3 1.00 0.75 36.17620 7.954546
Double Chex R cold 100 2 0 190 1.0 18.0 5 80 25 3 1.00 0.75 44.33086 6.125000
Froot Loops K cold 110 2 1 125 1.0 11.0 13 30 25 2 1.00 1.00 32.20758 7.565217
Frosted Flakes K cold 110 1 0 200 1.0 14.0 11 25 25 1 1.00 0.75 31.43597 7.565217
Frosted Mini-Wheats K cold 100 3 0 0 3.0 14.0 7 100 25 2 1.00 0.80 58.34514 7.565217
Fruit & Fibre Dates; Walnuts; and Oats P cold 120 3 2 160 5.0 12.0 10 200 25 3 1.25 0.67 40.91705 8.777778
Fruitful Bran K cold 120 3 0 240 5.0 14.0 12 190 25 3 1.33 0.67 41.01549 7.565217
Fruity Pebbles P cold 110 1 1 135 0.0 13.0 12 25 25 2 1.00 0.75 28.02576 8.777778
Golden Crisp P cold 100 2 0 45 0.0 11.0 15 40 25 1 1.00 0.88 35.25244 8.777778
Golden Grahams G cold 110 1 1 280 0.0 15.0 9 45 25 2 1.00 0.75 23.80404 7.954546
Grape Nuts Flakes P cold 100 3 1 140 3.0 15.0 5 85 25 3 1.00 0.88 52.07690 8.777778
Grape-Nuts P cold 110 3 0 170 3.0 17.0 3 90 25 3 1.00 0.25 53.37101 8.777778
Great Grains Pecan P cold 120 3 3 75 3.0 13.0 4 100 25 3 1.00 0.33 45.81172 8.777778
Honey Graham Ohs Q cold 120 1 2 220 1.0 12.0 11 45 25 2 1.00 1.00 21.87129 5.250000
Honey Nut Cheerios G cold 110 3 1 250 1.5 11.5 10 90 25 1 1.00 0.75 31.07222 7.954546
Honey-comb P cold 110 1 0 180 0.0 14.0 11 35 25 1 1.00 1.33 28.74241 8.777778
Just Right Crunchy Nuggets K cold 110 2 1 170 1.0 17.0 6 60 100 3 1.00 1.00 36.52368 7.565217
Just Right Fruit & Nut K cold 140 3 1 170 2.0 20.0 9 95 100 3 1.30 0.75 36.47151 7.565217
Kix G cold 110 2 1 260 0.0 21.0 3 40 25 2 1.00 1.50 39.24111 7.954546
Life Q cold 100 4 2 150 2.0 12.0 6 95 25 2 1.00 0.67 45.32807 5.250000
Lucky Charms G cold 110 2 1 180 0.0 12.0 12 55 25 2 1.00 1.00 26.73451 7.954546
Maypo A hot 100 4 1 0 0.0 16.0 3 95 25 2 1.00 1.00 54.85092 3.000000
Muesli Raisins; Dates; & Almonds R cold 150 4 3 95 3.0 16.0 11 170 25 3 1.00 1.00 37.13686 6.125000
Muesli Raisins; Peaches; & Pecans R cold 150 4 3 150 3.0 16.0 11 170 25 3 1.00 1.00 34.13976 6.125000
Mueslix Crispy Blend K cold 160 3 2 150 3.0 17.0 13 160 25 3 1.50 0.67 30.31335 7.565217
Multi-Grain Cheerios G cold 100 2 1 220 2.0 15.0 6 90 25 1 1.00 1.00 40.10596 7.954546
Nut&Honey Crunch K cold 120 2 1 190 0.0 15.0 9 40 25 2 1.00 0.67 29.92429 7.565217
Nutri-Grain Almond-Raisin K cold 140 3 2 220 3.0 21.0 7 130 25 3 1.33 0.67 40.69232 7.565217
Nutri-grain Wheat K cold 90 3 0 170 3.0 18.0 2 90 25 3 1.00 1.00 59.64284 7.565217
Oatmeal Raisin Crisp G cold 130 3 2 170 1.5 13.5 10 120 25 3 1.25 0.50 30.45084 7.954546
Post Nat. Raisin Bran P cold 120 3 1 200 6.0 11.0 14 260 25 3 1.33 0.67 37.84059 8.777778
Product 19 K cold 100 3 0 320 1.0 20.0 3 45 100 3 1.00 1.00 41.50354 7.565217
Puffed Rice Q cold 50 1 0 0 0.0 13.0 0 15 0 3 0.50 1.00 60.75611 5.250000
Puffed Wheat Q cold 50 2 0 0 1.0 10.0 0 50 0 3 0.50 1.00 63.00565 5.250000
Quaker Oat Squares Q cold 100 4 1 135 2.0 14.0 6 110 25 3 1.00 0.50 49.51187 5.250000
Quaker Oatmeal Q hot 100 5 2 0 2.7 -1.0 -1 110 0 1 1.00 0.67 50.82839 5.250000
Raisin Bran K cold 120 3 1 210 5.0 14.0 12 240 25 2 1.33 0.75 39.25920 7.565217
Raisin Nut Bran G cold 100 3 2 140 2.5 10.5 8 140 25 3 1.00 0.50 39.70340 7.954546
Raisin Squares K cold 90 2 0 0 2.0 15.0 6 110 25 3 1.00 0.50 55.33314 7.565217
Rice Chex R cold 110 1 0 240 0.0 23.0 2 30 25 1 1.00 1.13 41.99893 6.125000
Rice Krispies K cold 110 2 0 290 0.0 22.0 3 35 25 1 1.00 1.00 40.56016 7.565217
Shredded Wheat N cold 80 2 0 0 3.0 16.0 0 95 0 1 0.83 1.00 68.23588 1.833333
Shredded Wheat 'n'Bran N cold 90 3 0 0 4.0 19.0 0 140 0 1 1.00 0.67 74.47295 1.833333
Shredded Wheat spoon size N cold 90 3 0 0 3.0 20.0 0 120 0 1 1.00 0.67 72.80179 1.833333
Smacks K cold 110 2 1 70 1.0 9.0 15 40 25 2 1.00 0.75 31.23005 7.565217
Special K K cold 110 6 0 230 1.0 16.0 3 55 25 1 1.00 1.00 53.13132 7.565217
Strawberry Fruit Wheats N cold 90 2 0 15 3.0 15.0 5 90 25 2 1.00 1.00 59.36399 1.833333
Total Corn Flakes G cold 110 2 1 200 0.0 21.0 3 35 100 3 1.00 1.00 38.83975 7.954546
Total Raisin Bran G cold 140 3 1 190 4.0 15.0 14 230 100 3 1.50 1.00 28.59278 7.954546
Total Whole Grain G cold 100 3 1 200 3.0 16.0 3 110 100 3 1.00 1.00 46.65884 7.954546
Triples G cold 110 2 1 250 0.0 21.0 3 60 25 3 1.00 0.75 39.10617 7.954546
Trix G cold 110 1 1 140 0.0 13.0 12 25 25 2 1.00 1.00 27.75330 7.954546
Wheat Chex R cold 100 3 1 230 3.0 17.0 3 115 25 1 1.00 0.67 49.78744 6.125000
Wheaties G cold 100 3 1 200 3.0 17.0 3 110 25 1 1.00 1.00 51.59219 7.954546
Wheaties Honey Gold G cold 110 2 1 200 1.0 16.0 8 60 25 1 1.00 0.75 36.18756 7.954546

The Difference?

group_by() + summarize() collapses the data.

  • You will only have one row per group remaining.


group_by() + mutate() does not.

  • You will have the full number of rows remaining.

When would you need to ungroup()?

The default for summarize() is to drop the last variable after the subsequent operation is taken.

Meaning, the first variables used for grouping will not be dropped, unless otherwise specified.

. . .

cereal |> 
  group_by(manuf, type) |> 
  summarize(mean_calories = mean(calories))
`summarise()` has grouped output by 'manuf'. You can override using the
`.groups` argument.
# A tibble: 9 × 3
# Groups:   manuf [7]
  manuf type  mean_calories
  <fct> <fct>         <dbl>
1 A     hot           100  
2 G     cold          111. 
3 K     cold          109. 
4 N     cold           84  
5 N     hot           100  
6 P     cold          109. 
7 Q     cold           94.3
8 Q     hot           100  
9 R     cold          115

How do I ungroup?

Option 1 - Use the .groups argument of summarize()

cereal |> 
  group_by(manuf, type) |> 
  summarize(mean_calories = mean(calories), 
            .groups = "drop")

. . .

Option 2 - Use the ungroup() function after summarize()

cereal |> 
  group_by(manuf, type) |> 
  summarize(mean_calories = mean(calories)) |> 
  ungroup()

How do we “group” and “summarize” in base R?

You can use the aggregate() function.

cereal |> 
  aggregate(sugars ~ manuf, FUN = mean)
manuf sugars
A 3.000000
G 7.954546
K 7.565217
N 1.833333
P 8.777778
Q 5.250000
R 6.125000

Glue it all together!

cereal |> 
  filter(type == "cold") |> 
  mutate(potass_per_cup = potass / cups) |> 
  group_by(manuf) |> 
  summarise(mean_potass_per_cup = mean(potass_per_cup))
manuf mean_potass_per_cup
G 109.1970
K 175.3978
N 284.3089
P 203.8749
Q 93.3511
R 106.8864

Code Formatting

Similar to the + formatting in ggplot, do not continue a line after writing a |>!

cereal |> group_by(type) |> summarise(mean_fiber = mean(fiber), num_cereals = n(), mean_sugar = mean(sugars))
cereal |> 
  group_by(type) |> 
  summarise(mean_fiber = mean(fiber), 
            num_cereals = n(),
            mean_sugar = mean(sugars)
            )

PA 3: Identify the Mystery College

Today you will use the dplyr package to clean some data and then use that cleaned data to figure out what college Margaret has been accepted to.

A picture of a college building covered in green ivy. The building is reminescent of gothic architecture, with a brick exterior and many windows.

Finding Margaret’s College

This activity will require knowledge of:

  • debugging code errors
  • function syntax
  • logical comparisons
  • dplyr verbs and when to use them
  • chaining steps together with the pipe operator

. . .


None of us have all these abilities. Each of us has some of these abilities.

Pair Programming Expectations

During your collaboration, you and your partner will alternate between two roles:

. . .

Listener

  • The person who will type into the Quarto document in RStudio
  • Will not type unless prompted by the Problem Solver
  • Asks Problem Solver clarifying questions
  • Asks professor questions for the group

Problem Solver

  • Reads out instructions or prompts
  • Directs the Listener what to type in the Quarto document in Posit Cloud
  • Instructs the Listener what comments to make in the Quarto document to help the group understand the code later
  • Keeps group on task

Group Norms
  • Think and work together. Do not divide the work.
  • You are smarter together.
  • No cross-talk with other groups.

dplyr Resources

Every group should have a dplyr cheatsheet!

On the Front

  • Column 1: grouped summaries (group_by() + summarize())
  • Column 2: filter()ing values with logical comparisons
  • Column 3: select()ing and mutate()ing variables

On the Back

  • Column 2: summary functions you might like to use with summarize()

A picture of the dplyr cheatsheet, which contains helpful information on working with data in a variety of ways.

Opening the Practice Activity in Posit Cloud

The partner whose birthday comes last starts as the Listener!

They need to do the following:

  • Click on the PA2 link in Canvas
  • Log-in to Posit Cloud
  • Open the PA3-dplyr.qmd file (from the lower right corner)
  • Get started!

Submission

Submit the full name of the college Margaret will attend to the Canvas Quiz.

  • Each person will input the college in the PA3 Canvas quiz.
  • The person who last occupied the role of Listener will download and submit the PA-3.qmd file for the group.
    • Only one submission per group!

Wrap-up

What skills did you need?